Superweapon Surprise

"The statues are our sentinels: blind but ever watchful...those who deface or destroy them will know our wrath, unfettered and raw."

- Metroid Prime, Chozo Lore Scan

A people who seem weak or defenseless prove, emphatically, not to be.

Picture a peaceful paradise full of Space Amish; happy little sunshines who are not up to speed on technology. They are an inviting target for the Proud Warrior Race Guys. After all, there is the prospect of destruction and booty, but no chance of retaliation. The invasion is go!

The Space Amish whip out their previously-hidden defence system and blow the startled invaders out of the sky. It's the Superweapon Surprise! Not always a superweapon, but always a nasty surprise.

Comes in at least six flavors:
 * The Peace Vaults: They hide their weapons when there isn't any fighting.
 * Tool Conversion: They have no weapons, they just happen to have some tool which can double as an effective massive killing device. Weaponized Exhaust deals specifically with engines being used as emergency weapons. A massive industrial base that can quickly be switched over to produce war machines also works.
 * Bigger Brothers: They have friends who aren't weak or peaceable.
 * They are a Proud Scholar Race of Space Elves and/or Perfect Pacifist People who live in a City in A Bottle that is a Forgotten Superweapon of some sort.
 * They are a Sufficiently Advanced Alien species of unimaginable power who like to be low key about their abilities until their patience runs out.
 * They are a peaceful species- except for this one dude...

Compare Awakening the Sleeping Giant, where the civilization is known to be extremely dangerous, but something compromises their neutrality anyway.

Literature

 * The planet of Exocron in the Star Wars Expanded Universe novel Vision Of The Future is defended by a pretty pitiful defense fleet, which doesn't stand much of a chance against the powerful slaver fleet which tracked the protagonists there. However, it turns out the slavers were deliberately led to Exocron; the Aing-Tii monks, Force-users who usually don't go out of their territory but hate slavers, pop into orbit and, with their weird alien tech, waste the attacking fleet in a matter of minutes, then promptly leave again.
 * In Look To Windward by Iain M. Banks, free floating "airspheres" out amongst the stars host megafauna: extremely long-lived zeppelin-like creatures called behemothaurs. While intelligent, they appear to be easy targets. However, a mysterious transcendent race looks over the apparently hapless gasbags: any who mess with them tend to go extinct. At a species level.
 * Fred Saberhagen's "Berserker" short story "Sign of the Wolf". A human planet once had an advanced civilisation but all that is left is an automatic planetary defence system. When a berserker ship approaches and threatens to attack, a shepherd stumbles across an outpost of the defence system and inadvertently activates it, destroying the berserker.
 * Older Than Feudalism: Chapters 38-39 of the Biblical Book of Ezekiel (and, by extension, related passages in other books) is an example of this (the Bigger Brother is none other than God Himself).
 * This tends to be a common occurance throughout the The Bible. Any time an army beseiges Israel, they will inevitably encounter that one farmer still on good terms with the Almighty. This brings about many an epic Superweapon Surprise when the army of several hundred trained soldiers get slaughtered by a single farmhand with the Power of God. Or the ten-foot Phillistine supersoldier gets owned by a scrawny teenage shepherd boy with five rocks and a leather sling.
 * To be fair, slings are dangerous.
 * In Alastair Reynolds' novel Pushing Ice, the alien "McKinley" mentions this as one reason why they want to establish trade with the humans instead of just blasting them and taking what they want.
 * In James Hogan's Voyage From Yesteryear, a synthetically cloned Lost Colony of anarchist space-hippies are marked for cultural "re-assimilation" by an expedition from Earth. When every non-violent attempt at bringing them under the heel of typical culture fails absurdly in the face of the colonists' laid back outlook on life, the military might of the expedition is brought to bear... Only for an incredibly powerful weapon hidden in a crater on the planet's moon to blast it into oblivion. Interestingly the military delay their move until the colonists' orbiting spacecraft is on the other side of the planet, in the belief that it's a hidden-in-plain-sight Tool Conversion weapon. By this time, almost the entire expedition has already defected to join the colonists, leaving behind only the most dedicated follower of the General Ripper. In the story this was probably based on, Eric Frank Russell's "And Then There Were None", the ship simply left while it still had enough crew left to function. The colonists demonstrate that they are much more savvy and strategic than the military gave them credit for. They co-opt all the ground force as they can. When final mutiny aboard the miltiary warship begins, the colonist wait for the most dangerous hard-liners to make their escape in a shuttle craft. They knew that the worse rats would have a plan to flee the ship when it sinks; the General Ripper, his most essential loyalists and those that could pay for the privilege to abandon their fellow expeditionists. Then they blow the shuttle craft out of the sky. This is what is known as a decapitation strike.
 * In a Gordon R Dickson short story, an aggressive alien race discovers Earth by analysis of floating space debris and launches a covert surveillance mission as a prelude to invasion. Sadly for the aliens, they discover that the humans not only know about them, they used the alien mission as a tool to psychologically profile the would-be conquerors and find out all about their civilization and military capabilities.
 * In Alan Dean Foster's With Friends Like These..., a peaceful galactic federation faces attackers it cannot handle and in desperation turns to its outcasts, the historically militaristic, currently in quarantine on their homeworld, for help. The landing party is both amazed and disappointed to discover an almost pastoral planet of peaceful citizens that doesn't match their expectations at all -- until one of the local kids and their hosts, upon accepting their offer, reveal that . Which leads one of the vistors to seriously question what will happen once the war is won...
 * Several stories in Christopher Anvil's Interstellar Patrol setting used this trope:
 * In one, a human colony of pacifists not in the main human government is targeted for conquest by a nasty species. Turns out the colony is composed of people who don't want to fight because they are so badass that if they don't keep themselves under tight control they'd waste their own planet.
 * Another featured a peaceful, agrarian, planet. Where the local farmers had such bioengineering skill that the plants could eat the invading spaceships, let alone their organic crews.
 * And yet another peaceful planet topped that. Hard to successfully invade a world where the inhabitants have the ability to mentally control tectonics and the weather.
 * In Excession, The Culture puts whole war fleets in deep storage inside of asteroids other inconspicuous places after their last big war. Some of these depots might be moving into regions of space that could play host to events of interest... in a couple of centuries.
 * Timothy Zahn's Conquerors saga has the human Circe superweapon. It is kept hidden and unused until the last possible moment due to its extremely devastating effects (it burns starships from the inside out, cooking the crew alive). However, when the alien races are massing en force and defeat seems inevitable, the weapon is fired, and the resulting horror and surprise annihilation of the entire enemy fleet scare the other races into submission. The humans become rulers of known space, and force everyone to live peacefully in alliance, or else.
 * In The Inverted World, the inhabitants of the City regard the native "tooks" as hopelessly primitive, and savagely exploit them. Then it turns out the villages they've encountered so far were just the most badly impoverished in the area -- word of the City's rape and pillage has spread to other villages, ones that have rifles and grenades...
 * Although never attacked, China in the Temeraire Series is considered to be this. They have no standing army, and their dragons are more interested in poetry and math than warfare, but their breeding skills are remarkable so their dragons are all superior to their non-chinese counterparts, and they have a lot more, so if they were attacked, they can easily conscript a massive army.
 * David Weber's Out of the Dark has one that neither side was expecting. The alien Shongairi have invaded Earth and thoroughly trounced the conventional militaries of Earth. They hit a bit of a brick wall when trying to occupy Earth, however, as their weapons are designed to fight lower-tech enemies due to galactic laws against conquering technologically-advanced worlds. However, the war's outcome is still inevitable because the Shongairi sit in orbit and drop rocks on any major human military force. Things look grim for mankind, up until Mircea Basarab, leader of one of the human resistance groups, finally takes off the kid gloves and  and proceeds to   Who the hell saw that coming?
 * One sci-fi short story featured a philosophical version of this when the crew of an Earth Federation ship land on a pastoral (in that it lacked any population centers bigger than small towns) planet of pacifist socialist anarchists. Their secret weapon is a simple two-word philosophy . By the time the commanders of the ship realize how infectious the locals way of thinking and living is, half the enlisted men on the ship have gone AWOL and disappeared into the local population while half of those left are locked up drunk in the brig chanting the philosophy over and over in defiance. The Federation ship is forced to depart immediately, lest they lose any more essential crew-man and end up stranded because they can't even run the ship. They end up classifying the world as not worth conquering with a dangerously insane culture that warrants a social quarantine to prevent it spreading and infecting other places.

Live Action Television

 * The classic example is the Organians from the original Star Trek.
 * This Star Trek the Next Generation clip. Note that while a Federation Galaxy class starship is the most powerful Federation vessel up to that point and is by no means a pushover, it'd be hard pressed to defeat a single Romulan warbird, let alone two.
 * There are also the peaceful Eloi from the first season episode Justice. When Westley breaks a law, Sufficiently Advanced Aliens whom the Eloi worship as God, intervene to ensure the Enterprise does not escape.
 * Any planet in the Stargate Verse under the Protected Planets Treaty. Come what may, an Asgard starship can probably put a pretty big dent in it. Until the fifth season of Stargate SG-1, at least.
 * There is also the Nox in Stargate SG-1 who are very peaceful and even protect their would-be conquerors from the human expedition force (which is trying to protect them). As the humans go to leave, the Nox show, despite living a pastoral existence, have access to highly advanced technology far beyond humans and the Go'Aould.
 * 21st century Earth is, in the Whoniverse a backwater world way behind the technology level of the spacefaring civilizations that suround it. It's also the favorite world of the Doctor: a mad genius by the standard of his own species of nearly omnipotent Time Traveling aliens: threaten humanity's homeworld or hurt its inhabitants too much and you might remind him that he is way above Cthulhu in he food chain.
 * There's also the Torchwood One weapon used to destroy the.

Tabletop Games

 * Fairly common in Warhammer 40000. That Eldar Exodite/Maiden world with its peaceful bunch of space elves, or that Imperial Medieval/Feudal world may look ripe for conquest and corruption, but beware the Super Soldiers, massive battlefleets, and elf ninja clowns that the planet's distant rulers are liable to send when they receive word that one of their vassals is under attack.
 * On the other hand with the galaxy being so big, it may take days,weeks,or months for reinforcements to arrive.
 * Time to bust out the flame of Anor...

Video Games

 * The X-Universe games have the Boron, a peaceful aquatic race that asks for nothing more than to be left alone. The Split, the resident warmongers, aren't too keen on letting the Boron live peacefully, so they unleash their military machine and start a war that reduces the Boron presence in the universe to their home planet alone. The Argon (humans), the race that owns the largest part of the universe, take pity on the poor defenseless Borons and all of a sudden open a giant can of whoop-ass on the Split. The Split go "uh-oh".
 * During the games' timeline the Borons have been forced to take up arms, and have become pretty badass themselves. In the latest games the races often unleash military campaigns upon each other, and it's not at all uncommon to see a Split task force head to peaceful Boron sectors and promptly get smashed to pieces by the resident defence force.
 * In the Mass Effect universe, we have the Volus who are short and clumsy in their required enviro-suits. They would seem to be easy prey for the galaxy's pirates and slavers. However, mess with them and they'll call upon their Turian allies, who have the largest and most powerful military in the galaxy, for aid.

Western Animation

 * The Gargoyles at Scotland's Castle Wyvern were dismissed by the Viking invaders as intimidating stauary and legends ... then came to life at sunset and drove off the attackers. Unfortunately it didn't last, because gargoyles sleep petrified in stone by day, and the Vikings were able to shatter most of the clan two days later, ransack the castle and enslave all the humans inside. Which led to the survivors going after the Vikings to wreck bloody revenge, which led to the series premise.
 * In the premiere of Thundercats 2011, the Lizards have been the underdogs in their conflict with the Thundercats for generations. When the Lizards launch another attack on Thundera, King Claudus is confident that he can beat them back just as he's done countless times in the past. Unfortunately for Thundera, a powerful Outside Context Villain has conscripted the Lizards as his own personal army and armed them with Lost Technology such as missile-launching Humongous Mecha. The entire kingdom goes down in one night.

Anime and Manga

 * In Double Zeta Gundam, the heroes visited a Space Amish colony named Moon Moon (yes, that's its name), and naturally the evil Zeon empire followed the heroes there. Turns out the colony has an old-but-reasonably-powerful mobile suit left over from the colony's construction, that once reactivated, gave the heroes just enough of an edge (mostly through distracting the enemy) to fend Zeon's forces off.
 * Turn a Gundam has a variation with the Mountain Cycles scattered around Earth. They contain thousands of Mobile Suits in pristine condition that the Earthborn humans use to defend themselves from the invading Moonrace. The variation is that the Earthborn humans didn't know the Mountain Cycles existed either, only happening upon them by accident in the Moonrace's first attack.

Comic Books

 * Subverted in the origin story of Marvel's Silver Surfer: Zenn-La, Norrin Radd's homeworld, was a peaceful, highly advanced planet relying on a single awesome superweapon for protection, too...then Galactus came calling and it didn't even slow him down.

Film

 * In the animated movie Battle for Terra, humans have been forced into exile on a single ark ship by the destruction of all inhabitable planets in the Sol system (at the time: Earth Mars and Venus). When they discover a new planet that might support life, which they baptize Terra, there are a few problems. First, the atmosphere is unbreathable by humans. This can be solved with a terraforming device that can replace the atmosphere of the entire world. The other problem? It's inhabited by a race of peaceful flying creatures who live in harmony with nature and use only muscle-powered vehicles. Since the situation on the ark ship is desperate, the military commander wants to attack the peaceful aliens. The catch?

Literature

 * In Simon R Green's standalone novel Shadows Fall, the Elves have hidden vaults crammed full of multiple superweapons. When the Elves finally go to war, worlds tremble.
 * In The Eternal Champion by Michael Moorcock, the peace-loving Eldren (portrayed very differently by the humans) fit this trope. Even as they survive in their last city, all other cities taken over by humans, they refuse to consider using their arsenal of highly advanced weapons, using only weapons comparable to the primitive middle age weapons the humans have. Even if it means their extinction as a race. When convinces them to use their weapons, well, Curb Stomp Battle is a severe understatement.

Live Action TV

 * Stargate SG-1, the Nox. Except they're really a highly advanced civilisation with flying cities, which is just masquerading as Space Amish. While we never see them use any sort of weapons (they're still pacifists, and not of the technical variety), it's nearly impossible to find them if they don't want to be found. It's even harder to cause them real harm, since they can raise the dead, with the limits (if there are any) not being defined.
 * The Ancients somewhat qualify. Appearing to be all about Crystal Spires and Togas, except said crystal spires are in fact spaceships masquerading as cities with some some of the meanest weaponry around. The weapons in question are shown to be significantly superior to any and all modern-day Goa'uld technologies, despite the fact that over ten thousand years have passed since they were built.
 * The Tollan were an advanced Human civilisation who had developed their science far beyond Earth's and were well on their way to becoming the next Ancients. They are shown as peaceful and non-militaristic, but they did possess powerful ion cannons that could destroy a Ha'Tak in a single shot. Unfortunately for them, their technological prowess did not transfer into their military strategy which had all but atrophied. They naively trusted the Goa'uld, refusing to listen to our heroes as they considered Earth's civilisation as primitive. The deceitful Goa'uld inevitably developed countermeasures (as ) and wiped them out/enslaved them.
 * In one episode, the team finds a civilization that has given up all weapons except a mythical "sentinel" that is supposed to "send away" their enemies. The Goa'uld who have pretty much taken control of their planet understandably believe the "sentinel" doesn't exist. Turns out it's just broken . Once SG-1 gets it working again, every Goa'uld on the planet is indeed "sent away" to locations unknown. Well, they're probably just dead, but it seems that Never Say Die is an important part of the planet's society.
 * Subverted in "Thor's Chariot". The people of Cimmeria think the Hall of Thor's Might is one of these.
 * There was an episode of Stargate Atlantis where they go to a peaceful farming community that has a Cold War level technological civilization hidden underground to avoid drawing undue attention from the Wraith. Said community plays a role in several later episodes (sometimes as antagonists, sometimes as allies of the heroes), but its surface facade (while probably still existing) doesn't come up again because the heroes and the audience already know their secret.
 * It is implied in one of the episodes after the first that the entire surface facade is destroyed/culled when the Wraith find that there isn't enough food to go around.

Video Games

 * Can be utilized by players in the 4X RTS Star Ruler. Enemy players cannot determine how many ships a planet has docked (or if there are even shipyards on it). You could invade a ripe, seemingly undefended neutral player system with a couple ships, only for hundreds of their battleships to come swarming out of planets, with a Declaration of War in your diplomacy window.
 * In Star Control, the Chenjesu contacted Earth for help in an impending interstellar war because of our industrial capacity as well as our ability to be another bunch of warm bodies; they were pleasantly surprised to find out we also had a gigantic stockpile of unused nuclear weapons in our "peace vaults", hence the name of the subtrope.
 * Star Control II also has a variation: the Shofixti are hyperviolent honourable warriors and quite ready to oppose the invading Ur-Quan to the last furry little bastard. Nonetheless, they are only recently uplifted from savagery and incapable of fending off the gigantic Ur-Quan invasion fleets. So when the Ur-Quan fleet gets to the Shofixti homeworld, they respond by dropping a secret Precursor planetkiller bomb in the sun, causing a mininova and sterilizing the entire system. Surprise!
 * Star Control II has yet another one: when the Syreen surrendered to the Ur-Quan, they were forced to give up all their military hardware. The Ur-Quan put it all in a vault rather than destroy it, because they hate to waste anything. Once you escort a Syreen detachment to where the vault is, they become your own Sealed Good in A Can.
 * In the Fall From Heaven setting and backstory, the Elohim are a largely peaceful civilization, based around special ancient ruins, victims of wars, and such. Their worldspell matches this theme, by preventing enemy units from entering elohim territory for a certain amount of time. This can be used offensively, however, as units that would normally be needed for defense can be used to attack instead. In effect, the defending armies become the "peace vault" units.
 * The Bentusi in Homeworld are a race of peaceful traders. In fact, they're pretty much the only thing in the galaxy that isn't trying to vaporize you. But attack one of their ships? Well......you can see for yourself how well that turns out.

Film

 * In Jason X, moviedom's longest-running serial slasher got his ass handed to him by an android who, prior to a combat-upgrade to her software, was just some nerd's Sex Bot girlfriend. Yeah, of course he came back again, but that's gotta be humiliating!

Literature

 * Larry Niven's Known Space:
 * The warlike Kzinti stumble upon a completely demilitarised humanity. They invade, only to find out that reaction drives and solar sail launching lasers are actually pretty good at blowing things up. Surprise! This is referred to as the Kzinti lesson: "The more efficient a reaction drive, the more effective a weapon it makes." Related is Jon's Law which states "any interesting space drive is a weapon of mass destruction".
 * It isn't just the drive that's a weapon either, on at least one occasion a Bussard Ramjet ship itself was used as a RKV (Relativistic Kill Vehicle).
 * Another Known Space Niven example: the Wunderlanders managed to turn a mining tool into a weapon that carved a giant divot into a planet. A "divot" large enough to be visible from space, and deep enough to hold half the atmosphere and change the planet's ecology. It's called the "Wunderland Peacekeeper". And when humanity annexed the planet, they renamed it "Canyon" for obvious reasons.
 * Personal communication lasers are just tight beams for sending encoded messages. Shooting from the ground to a ship in orbit requires a bit of power to prevent blooming and errors, so the dial goes from "very low" to "reach orbit". Shooting it at someone 20 yards away when you're using the "reach orbit" setting yields... spectacular results.
 * An even more spectacular variant can be seen in Fleet of Worlds, where
 * The Puppeteers in Ringworld deny they carry any weapons at all, though it's something of a half-truth. For instance, their flashlight-laser just illuminates dark places. Don't tighten the focus too much, though: someone could get hurt. Louis Wu lampshades this fact in-universe. As Nessus is pointing out the devices he has brought on the expedition, and says "this is not a weapon", Louis notes the different ways they can still be used as weapons. Wu nicknames the ship "The Lying Bastard". Even a Puppeteer's natural weaponry is an example of this. Puppeteers are constantly running from trouble, not just because they're cowards, but because their physiology allows them to deliver backwards kicks that can kill people. Still mostly because they're cowards, though. Only insane Puppeteers actually bother with the lethal kick when they could be sprinting over the horizon. Which is sad, because the times we've seen a Puppeteer kick someone has always been awesome.
 * Human beings themselves, along with other mutated hominids, can be considered a Superweapon Surprise, seeings as they can, if they ingest enough Tree of Life, transform into Protectors, the (presumed to be lost) third developmental phase which features heightened intelligence, superhuman strength, increased pain tolerance, biological immortality, and an uncontrollable compulsion to protect members of their respective species. The entire human population of one planet was converted into Protectors in order to save Earth from the impending invasion of the Pak.
 * Robert A. Heinlein's The Moon Is a Harsh Mistress features the Moon colonists rebelling against the controlling Terran government. Earth laughs; the moon doesn't have the military capability to keep out Terran police. The Moon demonstrates that the launchers it uses to send grain shipments to Earth can also be used to drop big rocks on major cities. Also, converted mining lasers make reasonably good point-defence guns when properly cradled and controlled by a sapient super-computer.
 * In Stranger in A Strange Land, also by Robert A. Heinlein, the Martians seem to be bizarre, incomprehensible and inscrutable, but no real threat to humans due to their general lack of technology and very low key demeanor. Then it is discovered that they are . Oh, and.
 * Seen again in Heinlein's Young Adult novel Space Cadet. The Venusians are supposedly primitive, so a Jerkass Poor Little Rich Kid thinks he can push them around to get mining rights. It turns out that the 'primitive' Venusians are very good at chemistry, and use a powerful acid to burn into his ship and kill his crew. Later the Space Patrol is astonished when the Venusians synthesize fuel for their rocket. "They can do ANYTHING!"
 * Except play a harmonica.
 * In The Dragon Masters novella by Jack Vance, the Sacerdotes disdain conflict with the rest of the universe and profess to have no weapons. However, when the alien Grephs attack, a local chieftain tricks the Grephs into attacking the Sacerdotes, who convert the drive of the ship they are building into a weapon.
 * In Wedge's Gamble, a Star Wars Expanded Universe novel by Michael Stackpole, the Rogues discover that the Empire has been using this idea for propaganda: they have been claiming the Death Star at Endor was, in fact, a mining station that the Rebellion had commandeered and were going to turn on populated worlds. It proves to be an intriguing bit of foreshadowing, when later in the book Wedge and a couple of his teammates take over a skyscraper-sized construction droid and start ripping stuff up. And that's the distraction.
 * In Jedi Search scientist Qwi Xux, one of the designers of the Death Star, believes it was supposed to crack open dead planetoids for mining purposes, the World Devastators were automated mining vehicles, and the Sun Crusher was ... well, at that point she faces the fact that she was in denial. To be fair the World Devastators are really just scaled up automated mining vehicles that can also make stuff (like more World Devastators!)
 * More fittingly to the trope, after the crap hits the fan admiral Daala comes in with her Star Destroyers to try and stop our heroes as they're running away in the Sun Crusher. The phisically indestructible Sun Crusher. The ships open fire, but Han rams the stolen ship straight through a Star Destroyer's bridge, crippling the ship and sending it out of control into a black hole. Surprise!
 * Also in the Star Wars universe, the ThonBaka, a species of giant manta rays who just want to be left alone are attacked by the Imperials. Lando Calrissian helps them develop ways to drive them off, including "screaming" (which creates a massive electromagnetic pulse-style effect) and producing duplicates.
 * In Sergey Lukyanenko's sci-fi novels The Stars Are Cold Toys and Star Shadow, the Geometers are an advanced, altruistic civilization that has no weapons whatsoever, having supposedly outgrown warfare long ago. However, their many advanced tools can and frequently are used as weapons. They are a subversion inasmuch as they
 * In one of Lukyanenko's short stories, there's two of those going on, as well as rapid technology escalation. A grey arrives into a rural farmland and offers people gifts, but they already have their village utopia. Then he tries to invade Earth, but is thwarted with the use of this trope. Then he reveals himself to be Grey Goo, but his attempts to devour everything are thwarted again and he (and everything they devoured) is reverse engineered into what he was before turning into a grey goo by use of Earthians' femto-technologies.
 * In Shadows of Dreams, a powerful alien battleship arrives to a small human colony at relativistic speeds, thinking that the Vague War is still on. The Psilons invade and quickly subdue the colonists, waving off their feeble attempts at resistance. The protagonist finds one of the four bunkers used for planetary defense (the other three were destroyed by the Psilons during the initial bombing run) and manages to kill several Psilons in Powered Armor. Just as the rest of the colonists are about to be executed (the Psilons don't keep prisoners and only enslave those who have shown they can kill them), they offhandedly kill a member of the primitive indiginous race. Suddenly, a large number of the natives shows up and slices the battleship in half with a combined directed microwave attack. It was previously mentioned that anyone who slights a native can be fried to a crisp using their biological ability to emit directed microwaves. It's just that nobody thought that they could do that to a massive warship.
 * The star known as Elysium in Neal Asher's "The Line of Polity" is surrounded by asteroids that are mined and their ores smelted using a series of mirrors orbiting the star that can focus its light onto a single point. Guess what happens when the hero gets the big bad to chase him into this place.
 * In the Star Trek novel Infiltrator, the Next Generation crew comes upon a planet that had been colonized by other genetically-altered humans from Khan Noonien Singh's time who'd escaped Earth. Apparently they were quite peaceful, mostly content where they were, and unarmed...mainly because they were confident in their abilities to turn anything into a weapon if they had to.
 * In the novel Night Watch, the leader of a rebellion in Ankh-Morpork reflects that due to the anti-weaponry laws, his makeshift army doesn't have much in the way of real weapons--a few heirlooms passed down by veteran ancestors--but then, when his army consists of stevedores, longshoremen, butchers, and blacksmiths you pretty much have all the heavy or sharp objects you need. And if he ordered them to about face they'd make hash of themselves.
 * In ~James H. Schmitz~'s story The Tuvela (AKA The Demon Breed), a research biologist and a elderly researcher defeat an advance force of the Parahuan, intent on probing the defences of the Federation.
 * Iain M. Banks lives by this trope (see examples from the other subcategories): The Culture itself is also a nasty surprise. They are not Space Amish, they are Space Hippies. They spend their time having as much sex as they can, playing MMORPGs while sleeping, organizing parties, and just enjoying their very, very long lives. They are apparently so alien to discipline than even their equivalent of elite soldiers can wander off the battlefield if they feel like it. But the civilization is run by godlike AI, virtually any of their 30+ trillion citizens can be made into a Person of Mass Destruction, and their war fleets have little trouble blowing up planets or suns if they feel like it.
 * Aesop: When you have trouble with your neighbors and are able to quasi-instantly drop items into existence across star systems, consider sending them anti-matter.
 * It even happens on an individual level: the Sleeper Service appears to be a mildly eccentric GSV which has spent 40 years wandering the galaxy as a storage vessel for Human Popsicles. In fact it's
 * Don't Fuck With The Culture. It's a well known maxim. Nasty things tend to happen to people who do.
 * Or civilisations who do... or solar systems who do... And then you get Special Circumstances involved...
 * Sterilizing solar systems is nothing special in Cultureverse. The major galactic civilations there have weapons that can seriously damage stars. The better indication of the Culture's badassitude is the fact, that at least one of these civilizations, which has even better tech, most certainly isn't composed of space hippies, and does not like the Culture, still prefers to avoid a direct confrontation.
 * There are also a few sinister examples of ships that decide to not adopt the Culture's happy-go-lucky superficial appearance, and use that ridiculous amount of incredibly advanced technology for their own... not so happy-go-lucky activities. This is a good indication of what the Culture could do if it decides to get nasty. So it's probably a really good idea not to do anything that might influence them to change said happy-go-lucky nature. Grey Area (a.k.a Meatfucker), anyone?
 * Isaac Asimov's very own Foundation had an example of this. A customs inspection by the fading but still powerful Empire intercepts a trading vessel from said Foundation. During inspection, one of the officers accidentally turns an atomic drill at full strength on himself, illustrating this way that the Foundation should not be messed with since even their tools are weapons surpassing in power that of the Empire itself.
 * The book before that has a trader demonstrating a power tool... which you only need to reduce in weight a bit, and it will look quite in place on Obi-Wan's belt. The guy states that "the tool is dangerous, but so is a buzzsaw."
 * Stephen Baxter's Space has the Earth's population forced to Mercury, which alien privateer spaceships are encircling prior to coming down for the death-blow. One minute, the fleet is about to land - the next minute, Mercury appears to have exploded and the entire fleet is shredded into junk. The weapon?
 * In Vladimir Vasilyev's Antarctic Online, the entire continent of Antarctic swaps places with a bunch of island chains near the equator. The book deals with the consequences of the frozen continent suddenly becoming much a more favorable piece of real estate (even if it will take a few millennia to melt) for the world powers. A bunch of drunk antarctic researchers send out a radio message declaring independence, calling for the creation of the Free Antarctic nation. Despite half of the world supporting them (as they agree, it's not the half that matters), Antarctic finds itself blockaded by the US Navy and, eventually, outright invaded in a "peacekeeping action". Earlier, the Antarcticans start claiming that they have found an alien device in the melting ice that appears to be some sort of FTL drive that works by swapping two locations. They threaten to use it in the event of an invasion. Turns out it's just a bluff, which no one seems to be buying. Then, in the middle of the invasion, an American destroyer disappears and reappears in orbit. The President couldn't sign the order to pull out troops fast enough. It turns out that an Antarctican found a glowing orb with strange symbols on it buried in ice. Then he tripped and dropped it on the floor. The result was Antarctic moving to its new home. After using it to secure the sovereignty of the Free Antarctic nation, he buries it where no one will ever find it.

Live Action TV

 * Earth does this again in Doctor Who. Namely, they pull out a Death Star-like huge laser and shoot the Sycorax. Much to the Doctor's dismay, it was a shot in the back as they were fleeing.

Video Games

 * All (but one) of the Protoss units in Starcraft is originally derived from non-lethal craft and tools. Even the feared Reaver (with its horrifying Scarabs), originally built for mining. (Well, that's what they say...) In Brood War, the Dark Templars' units were designed as weapons from the start, because they weren't a unified species and thusly had to fight. (With the Protoss more hard-pressed after Brood War's Downer Ending, for the forthcoming sequel they're dusting off their old war machines from before their races was "unified" by the Khala--and finally starting to invent new ones.)
 * Many people forget that the Blue Bomber himself, Mega Man, was originally a household servant robot. When Wily decided to get all Jerkass and take over the world, Rock was repurposed into a fighting robot. This, in itself, is not the superweapon surprise. That comes when Rock's Variable Tool System, designed to allow him to use any tool without needing new instructions or programming, is also redesigned into Mega Man's Variable Weapon System, allowing him to use any weapon without serious modification to his systems. So the household cleaning robot instead becomes a superweapon of destruction, capable of getting an infinite number of new weapons at any time. Surprise!
 * Partial example: In The Moon Project the Lunar Corporation's strongest weapons - a sonic cannon - is derived from a modified mining tool.
 * Though the people using it weren't exactly de-militarized (You're piloting a Humongous Mecha, after all), the instruction manual to Ranger X describes the game's BFG as being "originally designed to aid in tunnel digging." This is the only weapon in the game that, upon firing, pierces any and all obstacles and shifts the game camera to the right as it goes. Who would have thought a tool designed to dig an entire tunnel in one to three shots would be more effective than any other weapon your mech can possibly find?
 * Both inverted (weapons turned into tools) and played straight in Command and Conquer 3: the GDI have sonic weapons and after the 2nd war they discover that sonics can destroy submerged tiberium so the technology is made into emitters to protect the cities. Years later when the Scrin are kicking GDI's ass someone figures out that their biology is heavily dependant on tiberium and promptly turn the emitters back into weapons which devastate the invading army.
 * Somewhere between Tool Conversion and Open the Door And See All The People with the TEC in "Sins of a Solar Empire"; while the TEC don't seem completely defenseless and are certainly not very peaceful, they are nowhere near as unified as the Vasari, and are of a far lower level of technology in many respects. This, combined with the Vasari's failure to scout ahead far enough before invading TEC space, causes the Vasari to severely underestimate them, thinking that they are just another small, low-tech race to eradicate. The Vasari then attack a human system, and have to fight tooth and nail against cargo ships and merchant vessels retrofitted as warships, but finally take it. Then they look a little harder at the sector they've just invaded, and realize that one system they fought so hard to take was one of hundreds of thousands oh human-controlled systems. Whoops.

Western Animation

 * In Transformers Animated, Word of God says the Autobots mostly just have tools to defend themselves with, while Decepticons only have explicit weaponry. Guess who wins.
 * The ones with the giant, heavily armed Omega Sentinels?

Real Life

 * The United States lived by the "massive industrial base" conversion part of this trope up through World War 2. Though the US never had as large of a standing military as the European powers during that time, they could easily convert their massive industrial complex to create weapons of war. Factories which produced automobiles or appliances would be quickly converted to produce tanks, planes and bombs during the war. This was further supplemented by the fact that when the men went off to fight, the nation's women would take over in the factories to produce the supplies. The US was a rare example of a nation that would often come out of a war with greater military strength than when they went in thanks to this.

Anime and Manga

 * Not quite a peace vault per se, but the principle is the same in many of the Tenchi Muyo continuities. If there are space pirates and would-be conquerers, why not set their sights on Earth? Simple: Ryu-oh, Tsunami and Ryo-ohki are all resident on the planet; any of these ships alone could fend off any enemy fleet save for Jurai's. Speaking of which, members of the Jurai Royal family treat the planet as their home away from home including their crown princess. Attacking Earth will likely bring Jurai's fleet down on you like the wrath of the kami. Plus there is this one guy called Tenchi Masaki who has a thing about conquering his homeworld... So I guess its a three-in-one superweapon surprise in the Tenchi universe? Especially big in OVA continuity, where Earth is specifically a two-bit colony world that nobody cares about. Except for the above things. Oh, and Washu, the genius scientist who could destroy a planet by accident. Mihoshi has incredible luck, to the point where she can accidentally solve any case. Oh, and there are Tsunami's sisters...Who are goddesses.
 * Oh, and they're all on the same side. So basically if you're serious about messing with Earth, you're facing all of the above.
 * Oh, look at these puny Lilim (AKA humans). They are so much smaller than us Angels born from Adam. They can't even generate a useful AT-field. So what if a small number of them know that we're coming, they have nothing to defend against us except for explosives that can't penetrate out AT-field. Oh, what's this giant purple humanoid thingy? An Angel wannabe? Oh, look, it can't even walk properly! I'll just punch through the eye; that was easy.....Huh? It's still mov- OH CRAAAAAAAAAAA-

Comic Books

 * Star Wars Legacy: The newly resurrected Darth Krayt had a secret army of Sith Troopers which caught the Alliance off guard.

Film

 * The cute and fuzzy Ewoks of 'Star Wars'' once mopped up some of the best and the brightest of the Empire. Whether this was a matter of sheer numbers or supernatural organizing skills and the ability to quickly upgrade their tactics is a topic left only to the most eccentric of Republic scholars.
 * Partial subversion. While the Ewoks can kill troops with relative ease, it takes a lot of effort and some brave decoys to destroy the few walkers they do get; it's Chewbacca who really turns the tide.
 * The original script called for Endor to be populated by wookies, but they switched them for much less awesome muppets^h^h^h^h^h^h ewoks to stay under budget.

Fanfic

 * In the Buffy the Vampire Slayer/Doctor Who crossover The Impossible War, the Daleks invade modern-day Earth. As expected, human technology is woefully inadequate. Human magic on the other hand...
 * In the Mass Effect/Command and Conquer crossover Renegade, the Turian Hierarchy invaded the human colony world of Shanxi just like the did in the canon timeline. However, Shanxi is held by the Global Defense Initiative, and the turians catch a face full of ion cannons, rapid-fabrication technology, and house-sized tanks of "fuck you".

Literature

 * Frank Herbert's Dune provides a clean-cut example of the Hidden Badass variety. On the remote outskirts of god-forsaken planet, in the huge desert, a small bunch of ragtag people scavenge for a living. Do not get trigger-happy yet: those people are, infact, bred by their demanding enviroment to be the best fighters in Universe. And their numbers are seriously underestimated... Long story short, a hundred years and several books after being bothered, they sweep their Jyhad holy crusade across the Galaxy. Woops!
 * Subverted in Animorphs, with an alien race of Precursors called the Pemalites. The Pemalites had great technological power, and used it only for peaceful and playful purposes. They were invaded and destroyed by another race called the Howlers. It's explained that they could have forged their plowshares into swords, could have repelled their invasion, but they chose not to do it because they couldn't bring themselves to become violent killers. So they were destroyed, and their memory is a cautionary tale against the dangers of pacifism.
 * In a later addition, it turns out that they were created by the Ellimist, and programmed to have such an overwhelming love for life that they could never kill. They ended up dying while the Ellimist was otherwise occupied. The poor guys never had a chance.
 * No, the Ellimist only guided them along that path, as it couldn't directly intervene due to its Xanatos Speed Chess match with the Crayak- same reason it didn't protect them. And its worth noting that the essence of the Pemalites was later incorporated into Earth wolves to create dogs.
 * Played straight with the Pemalites' androids. Although simarly loaded with pacifist protocols, they are are super strong.
 * The Harshini in Jennifer Fallion's Wolfblade are a race of extreme pacifists possessed of great magical power, but incapable of defending themselves with it, so the people of the nation of Medalon can kill them off for no reason whenever they find them. Except for this one guy, Brakandaran the Halfbreed...
 * Shadows of the Empire has a good one. The Suprosa is an apparently harmless freighter that the Rebels suspect is carrying the plans for the second Death Star. When they attack, the Suprosa deploys its weapons, including a diamond-boron missile launcher that takes out half of the attackers. Remember the "many Bothans who died to bring us this information"? That was the Suprosa.
 * Also seen in Rebel Dream, when Czulkang Lah discovered that
 * The Dragonlance short story "Wayward Children" is about a group of draconians who have occupied a small, peaceful elven village. There are no children in this village, which the draconians think is a little unusual. Following a magical attempt to turn the draconians back into what they were made from - which fails - the draconians discover that the "elves" are actually silver dragons. Cue death-screams.
 * Alan Dean Foster's The Damned series. The real superweapon is Humanity itself, bred on a world with chaotic geology and weather, thus stronger and tougher and more adaptable than most, and capable of dealing with the insanity of war and enjoying it. Oh, and non-human telepaths that try to enter our minds go into catatonia.
 * The attempted Haruchai invasion of the Land in the Backstory of The Chronicles of Thomas Covenant is this trope. The Proud Warrior Race in question thought that the peaceful hippies of the Land would be easy pickings. It turned out said hippies wielded powerful nature magic that the Haruchai had no counter for. The invasion didn't amount to much, and in short order the Haruchai found themselves in debt to the people of the Land for their mercy.
 * The Algebraist by Iain M. Banks: the Dwellers, a bumbling, if ancient, race of gas-giant aliens reveal that their tech is vastly superior to the junk with which they are normally credited: Also consider that if you really piss off Dwellers, you can expect to find a planet sized collection of rocks, gravel and dust impacting your home world at a great proportion of the speed of light.
 * In one of the books in the Worldwar series, as the Race prepares its invasion of Britain: Churchill warns that any invaders will have to face his most horrible weapons. No, he's not talking about nukes.
 * Ships are also a big surprise to the Race, although not of the superweapon type (except when one is used ). They've never seen any body of water bigger than a lake and never bothered to develop sea travel or naval warfare.
 * Invoked In-Universe in Enchantress From the Stars. And advanced spacefaring civilization invades a world that is still in Middge Ages and intends to rout and enslave all locals. This is discovered be The Federation, and even more advanced civilisation which, however, has an Alien Non Interference Clause prohibiting them of overtly takoing position. So they plan to get the Empire to withdraw by convincing them that local people have supernatural powers like telekinesis.

Live Action TV

 * The Organians from Star Trek the Original Series: sometimes the Space Amish turn out to be Sufficiently Advanced Aliens and don't need superweapons.
 * In Star Trek Deep Space Nine, the Klingons came in with an armada to take the puny station. Captain Sisko informs them that the station has been upgraded, and is quite willing to show what happens when The Federation puts their minds to arming themselves. The station puts the fleet through a grueling meat grinder of a battle.

Video Games

 * Cleverly subverted in Command and Conquer 3, where the Sufficiently Advanced Aliens fall prey to Kane's diabolical Xanatos Gambit. It turns out that the aim of the liquid tiberium explosion (engineered by Kane) was to trigger a premature alien invasion of Earth, permit the still-powerful GDI to slaughter the aliens, then recover their technology. This is reflected in the Scrin campaign, where initial confidence quickly gives way to damage control, followed by a hasty evacuation of the invading forces. They only helped Kane's Evil Plan along.
 * Done straight in Fire Emblem the Sacred Stones. Myrrh appears to be a shy, young little girl who seems harmless. But when equipped with her Dragonstone, she transforms into a huge-ass Dragon who can kill almost anyone with one shot.
 * Metroid has the Chozo: peaceful bird-like people who lived in harmony with nature. Also were once the single most technologically-advanced race ever. Vanished without a trace by the time the series continuity starts, but their remnant technology demonstrates this trope well. In particular, their statues, while decorative and ceremonial, also function as guardians of important places to the Chozo: Ridley, in Prime, blew up one of their temples trying to kill Samus, and got six giant lasers to the chest for doing so (after Samus beat him into the ground). Samus is the only Chozo soldier present in the known universe, and that's enough to give nightmares to the most ruthless race of the galaxy, (essentially Xenomorphs with a technological level approaching the Culture's)
 * A variation occurs in Unreal II the Awakening. Most of the game involves a hunt for what you think is a superweapon. The actual super weapon turns out to be a race of seemingly-harmless aliens that perform various menial tasks. The "superweapon" you were collecting was merely an activation key that takes them out of this "dormant" form, into their true form -- giant unstoppable killing machines that can shoot black holes from their hands. No, really. Unfortunately, it really is only an activation key -- it provides no control, so the new supersoldiers rampage through the ship this was tested on and you have to reroute it into the nearest star and escape alive.
 * In Sid Meiers Alpha Centauri, the Gaians--and, in the expansion, the Cult of Planet--seem like rather wimpy factions, what with being more concerned with environmentalism than proper defense training, a lucrative economy, or developing weapons technology. That is, until you find that their devotion to the environment also gives them an innate ability to take control of the extremely dangerous mindraping, live-brain-devouring native fauna of Planet. Did we mention that said fauna is equally threatening to unarmored infantrymen carrying ancient guns and your best tanks armed with literal black hole generators and armored with space-time itself? You don't want to know what they can do once they figure out how to breed their own...
 * In Galactic Civilizations, the computer determines actual military power based on the number and power of warships in your empire, and forgets about the technological advantages, industrial base, and massive treasuries. No, I don't have any warships. Next week, I can have a fleet of battleships, dreadnoughts, and destroyers ready to wipe you from space.
 * The Liir from Sword of the Stars are normally pacifistic and were targeted for enslavement by the "Suul'Ka" for it. The enslavement led to two things: Firstly, that the Liir will turn directly from The Fettered into The Unfettered when pushed too far and stay that way, and two, that their innate skill with technology renders them really good at making bio-weapons of 'extinction'-level virulence and turning their (now exterminated) captors' techology into a workable technological basis for making starfleets.
 * Since then, we have gotten a bit more of a view of the Sot S universe. The Suul'ka in question are the insane Liir elders who in an attempt to avoid their inevitable death by crushing enslave the entire Liir race and run them through rapid industrialization in order to have them build a massive spacesuit they can live in. After the last time this happened the Liir rose, led by the Black and decided that they weren't going to let that happen any more. Oh and that they were going to go ahead and get rid of those insane elders already in space. Cue most of the Suul'ka dying. A few got away though and as of Sword of the Stars 2, they're back.
 * This also means their story of using a bioweapon to wipe them out is complete bullshit created for PR purposes. Since the Suul'ka are about a dozen individuals that have no physical contact with one another, using a virus doesn't make any sense, especially since the Liir would be more likely to infect themselves, as they're the same species.
 * Actually, it was a bioweapon. Or more specifically, a Living weapon
 * In Cave Story, Mimigas once ate flowers that made them into Killer Rabbits as a last resort to thwart an invasion. It's so secret they no longer know it.
 * When the Orcs of War Craft initially sent scouts to Azeroth, they saw peaceful meadows tended by farmers, and quickly came to the conclusion that they would roll over the population. Instead, the Azeroth soldiers and knights crushed their initial attack. The orcs regrouped and invaded more successfully later, but them being on the business end of an asswhuppin' came as a shock.
 * The main reason they won was because King Llane was assassinated by Garona, whom he trusted. Until then, Stormwind held out fairly successfully. It was the strongest of the Seven Kingdoms, after all.
 * The game Immortal Defense has people ascended to pathspace to serve as the One Man Armies meant to destroy the oncoming invasion of the Bavakh. You are one such of these people.
 * The Volus in Mass Effect have only a single Dreadnought... that packs enough firepower to roast an entire planet three times over. There's a reason they don't need two.
 * In Mini Robot Wars, the titular MiniRobots are Mechanical Lifeforms who are initially overwhelmed and captured by the invading Machines. They actually have many battle-capable units who are able to destroy and repel the invading Machines, but the MiniRobots are peace-lovers and were not prepared for war.

Web Comics

 * Girl Genius has a rather weird case in the city of Mechanicsburg, which was the home of the Heterodyne dynasty - Sparks crazy even by the Sparks' standards. This obviously means the city is, in fact, a death trap looking like a city. However, since the dynasty is presumed to have died out and only a Heterodyne can properly use it, nobody expects the stuff to be used. Then, Klaus Wulfenbach (ruler of most of Europe due to his politics of "don't make me come over there") is incapacitated - in Mechanicsburg. This quickly starts a free-for-all war with Mechanincsburg as the battleground. Guess what happens.
 * Then, the armies actually overcome the resistance; weakened, but still too powerful to beat...and then the Jägers arrive.

Web Original

 * In The Salvation War, the forces of Satan invade the Earth  expecting a curbstomp. Too bad the demons are at bronze age levels of technology and haven't been keeping up to date on recent human history. As it happens, there IS a curbstomp... right about when bronze meets the M-1 Abrams MBT. Surprise! Also a surprise to Incomparable Legion Of Light when

Real Life
"Swiss General: If you invade us, we can mobilize half a million men to defend our country.
 * The atomic bomb dropped on Hiroshima.
 * The Kamikaze, the Kaiten torpedo, and the Baka bomb. At a stage when the US had already essentially won the war as long as they kept fighting, these suicide weapons were a most unpleasant surprise.
 * Ninja (as in real Ninja) weapons were all derived from farm implements and often disguised and used as such so that they can carried and used in the open. Keep in mind that, at least from the beginning, Ninja were strictly defensive clans allied against oppressive samurai.
 * The shillelagh, in Ireland (and, no, not the little, short cudgels passed off to tourists as shillelaghs, nowadays). The knob on the end of that "walking stick" can pack quite a wallop, especially if it's filled with lead (referred to as a "loaded" stick). Though it could be argued that this doesn't apply that well to the trope in general, as few with any sense of history would describe the Irish as "peaceful".
 * Costa Rica has no standing army to speak of whatsoever. Instead, they have a defense pact with the United States and the United Kingdom, who have pledged to send immediate military aid upon the threat of invasion. ("Hey guys, I don't have an army, can I borrow yours?")
 * Go ahead. Attack Costa Rica. I DARE YOU.
 * Argentina invaded the Falkland Islands because the islands were completely undefended (the only British "military" asset stationed there at the time was an Antarctic research ship, and even that was about to be pulled out) and they believed the British simply had no real desire to try to retake them, especially in the face of proposed defense cuts. Then they invaded; then the British got pissed, and sent anything they could to the South Atlantic, including postponing the retirement of their Vulcan bombers (and pulling some out of the boneyards), originally scheduled for retirement early that year and doing an emergency cancellation of the sale of the aircraft carrier HMS Hermes (one of only two the Royal Navy had at the time) to the Indians when the ink was still drying (and completely scrapping the sale of the other one, HMS Invincible, to the Aussies), so you can argue it fits the above trope as well.
 * New Zealand has a very small military, retiring the last of their tactical combat aircraft in 2002 and their largest warships are under-gunned frigates; yet they possess some of the most respected, well-trained and highly capable special forces teams in the world (some have argued they're better than what the US can put out), and have been on nearly continuous overseas deployment during The Nineties and since the turn of the millenium.
 * Australian soldiers are renowned for being very professional and excellent at teamwork (though not always at taking orders). Small population countries do the best with what they have.
 * Switzerland. Yes, eternally neutral. Good bankers and watchmakers. Want to stomp on them? Feel like walking into a small, mountainous region where every able-bodied male is conscripted into the military when they turn eighteen, serves until the age of thirty (sure, it's only three weeks a year, not unlike the National Guard, but still), and is required to keep an assault rifle and 50 rounds in his house at all times? Many choose to retain their service weapons as hunting rifles as well... About the only thing dumber than an invasion of Switzerland would be starting a land war in Asia.
 * A famous Badass Boast:

Wehrmacht General: And what if the Fueher invades your country with one million men.

Swiss General: We will shoot twice."


 * Canada, while not any more or less militant than most first-world countries, their biggest means of defense even before their own armed forces is that they're right next to the almost absurdly well-armed United States of America. Any serious threat to Canada, pretty much by definition, would be at least as dangerous to the US, which would respond in kind.
 * Really, this applies to almost any nation in the Western Hemisphere, due to long standing (all the way to Monroe) U.S. policy. Unless the USA itself invades you, of course.
 * Iceland and Luxembourg have essentially no military forces but are members of NATO.
 * Despite the fact that their constitution explicitly prohibits militarization, Japan's "Self-Defense Forces" are in the top ten largest militaries in the world.
 * Israel essentially pulled this in the Six-Day War.
 * Half a century later, Lebanon's Hizbollah pulled something similar. Not so much Superweaponing as massive Underdogging.
 * The 2008 South Ossetia war: the Georgian government thought that the Russians wouldn't care what happens when they invade that little, unstable secessionist region between their borders and killing hundreds of Russian citizens. They were wrong.
 * Finland during Winter War. The Soviet Union was certain they could conquer the entire country within a span of few weeks. Instead, the plucky little place resisted for a hundred days and made their enemy pay a heavy price for every mile they acquired. Technically the Soviets did win, and they could have kept going and eventually crush the Finns, but it more than qualifies regardless. Besides, Finland had a One-Man Army Simo Häyhä, who practically qualifies as a superweapon in his own right.
 * Inverted during World War II when the Japanese grabbed an atlas, took a look at the size of Australia and believed that a successful land invasion would be utterly impossible. Even if every able bodied Aussie alive at the time was armed and ready, they still wouldn't have enough troops to defend themselves as their population was only a bit over 7 million. Even now, they only have a bit under 22 million (the majority of the population is within a couple hundred miles of an ocean coast - the inland is primarily desert and almost entirely unpopulated). On the flipside, they do have large uranium deposits and the know-how to make them into something explosive.
 * The siege of Syracuse 215 B.C. . What was supposed to be a quick assault turned into a three year siege. Credited to the wonderful devices of Archimedes. As the biographer Plutarch put it "When, therefore, the Romans came up under the walls, thinking themselves unnoticed, once more they encountered a great storm of missiles; huge stones came tumbling down upon them almost perpendicularly, and the wall shot out arrows at them from every point; they therefore retired.... . At last, the Romans became so fearful that, whenever they saw a bit of rope or a stick of timber projecting a little over the wall, “There it is,” they cried, “Archimedes is training some engine upon us,” and turned their backs and fled."
 * Other accounts also include hidden hooks and pulleys that could tear ships apart if they got too close to the walls and arrays of mirrors used as Death Rays by focusing sunlight to burn ships.
 * The last of which was busted by Myth Busters.