Humans Are Warriors



""We poison our air and water to weed out the weak! We set off fission bombs in our only biosphere! We nailed our God to a stick! Don't fuck with the human race!""

- A forum post (Post 2710017, NSFW)

Somewhere between Humans Are the Real Monsters, Humans Are Special and Humanity Is Superior lies this trope, the polar opposite of Humans Are Diplomats. Compared to the other races of the galaxy, or at least the other 'good' races, humans are violent, warlike savages who revel in chaos and destruction. This is not, however, a bad thing; at worst, the more 'civilized' races may look down on us, but they acknowledge that we're not a plague to be wiped out. Or at least they acknowledge that it might be somewhat inadvisable to try.

The trope takes one of two forms:


 * In the first form, humans are helping themselves with their savagery; the technologically, physically, and/or mentally superior aliens would wipe us out or enslave us if not for our courage, tenacity, and willingness to pull crazy stunts in battle and the experience of thousands of years of conflict. Look for humanity to attempt to capture and reverse-engineer as much of the aliens' superior technology as possible, while aliens either keep the pressure on through sheer resource advantage or begin to learn some of our own tricks to turn against us. Other aliens, inspired by our example, may rise against their keepers or speak out on our behalf in the Galactic Senate, so we can eventually come to have claim to our space that we don't have to constantly fight to protect. This version is frequently related to Earth Is a Battlefield.
 * The second form of this trope makes humans useful to other aliens. Maybe the 'good' aliens have been fighting a losing war against the 'evil' aliens due to psychological limitations, numbers, or lack of training in the art of war. Maybe they are evenly matched or even winning against the enemy but want someone else to get shot at for a change. By working together with humans, they can actually put their advanced technology to use effectively; in turn, humans gain the peacetime benefits of the aliens' advanced technology. Other aliens may be less scrupulous about the relationship, considering us less 'valuable partners' and more 'Battle Thralls'. So long as they are able to enforce the relationship through their technology, this trope remains in the second form... but expect us to keep an eye out for a chance to break free of our insect overlords, no matter how benevolent they seem.

A variation on this trope might be called "Humans Are Soldiers." In this case, far from being pacifists, the aliens are a Proud Warrior Race- to the max. Problem is, they're so focused on honor duels and personal-scale violence, they can't bring together armies and fleets, or are simply ineffectual when they do because they won't or can't cooperate and establish a chain of command. Thus despite actually being less skilled at raw violence, humanity ends up being the ones able to band together and fight wars, and fulfill this trope.

Anime and Manga

 * Guyver: With the human villains, Chronos, who find Uranus technology, reverse-engineer it, make far more powerful versions of it, and plan to use it to find the Uranus and kill them.
 * Robotech: A series about an alien ship that crashes on earth giving humans access to advanced technology. Humanity weaponizes the tech and not long after finds itself embroiled in war with giant aggressive humanoid aliens over a powerful energy source.

Fan Fiction/Fan Works

 * Renegade: The Command & Conquer/Mass Effect crossover. Humans are essentially this. The main strength of humanity is that they became tough, strong, resourceful, and resilient because they were surviving on a world where the very ground was trying to kill them. As a result, they developed a mentality of aggressive, conservative militancy and devised advanced technology to simply survive on their homeworld. Once they got off Earth in large numbers (thanks to mass effect technology) they turned the same Green Rocks ravaging their homeworld into the means to fund an aggressive expansion into the galaxy, which subsequently allowed them to form a political/military bloc independent of the Citadel. Between their tech, mindset, and economic power, GDI became a major player in galactic politics mere decades after making First Contact.
 * Its prequel, Eagle's Fall, goes into detail on this, at least with regards to the turians' reactions during the war on Shanxi. The GDI humans' ferocity and technology forces the Hierarchy's troops into a brutal ground war that costs them a tremendous amount of lives and equipment, and while the human defenders are eventually overwhelmed, they force the turians to respect their capacity for violence.
 * XSGCOM series: Being a fusion of the Stargate series and the X-COM series, is a definite example of this. Being the spawn of two examples of this trope, the crazy insanity and massive explosions are only ramped up. P90's? Try elerium plasma weapons stolen from renegade Asgard. The Goa'uld bring in the staff weapons? We steal those, cut them up, and make Gatling Staffs and Gatling Staff Cannons. Loki unleashes psychic troops? We bring out our own. The Kull are a problem? Bring out the Power Armor with more weapons than a decent-sized army. Wraith attacking Atlantis? Hello, orbital Naquadria weapons!

Film
""Humans... They are not the cowering wretches we were promised... They stand. They are unruly and therefore cannot be ruled. To challenge them is to court death.""
 * The Avengers:


 * Battle Beyond the Stars: Space Cowboy, who is a member of just one of the Proud Warrior Races needed for this job. He is also the only character in the whole movie who is actually from the planet Earth..

Literature
"Allison: "You think you know us. You know nothing. You’ve seen the world through the eyes of a defeated soldier and a junkie bimbo. You know nothing. We’ll defeat you, Edriss.""
 * Animorphs: Where various aliens (usually Andalites) note just how vicious a place Earth is and how addicted to fighting each other humans are, and wonder if the Yeerks knew what they were getting into.
 * Stated almost flat-out by one of Visser One's hosts:


 * Central Control stories by Andre Norton: Where upon making first contact with the rest of the galaxy, humanity was deemed too savage to be allowed free run of the place. Instead, humans are only allowed to go off world as sort of Space Hessians.
 * Death or Gloryby Vladimir Vasilyev: Humans are one of the weakest, technologically-backward races in the galaxy. While we have finally figured out FTL travel, it's extremely slow and costly. The major worlds (including Earth) are suffering from pollution and overpopulation. The outer colonies are, basically, Wild West In Space. The alien races, for the most part, avoid humanity, as they consider intelligent primates to be an evolutionary mistake (our bodies are too complex for our own good), and only pay a visit when they want to demand some resource or other. A chance discovery results in humans getting their hands on an extremely-powerful warship, capable of obliterating entire worlds and fleets. When the aliens arrive to the human colony, they send troops to capture all colonists... who promptly get their asses handed to them by the angry prospectors and the local garrison. Then the colonists capture the ship, blow up their colony, and leave. The aliens catch up to them and offer full membership in The Alliance, calling humanity a "latent" race. In books 2 and 3 of the series, a former slave race of one of the Alliance members rebels and proceeds to wipe the floor with most of the Alliance races with their massive armada, which no one somehow caught them building. Guess who's the only race to successfully resist the new empire? The other races are smart enough to realize this and try to work in tandem with humans.
 * In the third book, an enemy armada blockades a jungle world that contains a safari. The enemy sends in troops to capture any planetside humans. They get beaten by a bunch of tourists, (admittedly, their guide is pretty good, and one of them is actually a spy on vacation).
 * Empire From the Ashes: The Achuultani refer to the human chunk of the galaxy as the "Demon Sector" because their periodic genocidal waves always suffer huge losses there.
 * The Forever War:During their first confrontation, the opposing Starfish Aliens don't even know what a one-on-one battle is about.
 * "The Gentle Vultures": A short story by Isaac Asimov, there is a group of aliens on the Moon waiting for World War III to start. They detected the Hiroshima and Nagasaki bombings, and thought a nuclear war would soon begin, but fifteen years later it hasn't happened at all. The alien in charge discovers that, even if we aren't at war, we are still way too good at it (making new, more powerful nukes, of course). We are so good that the we are developing war technology in peacetime even faster than we would have if war had broken out.
 * The High Crusade: The medieval English quickly show a bunch of downtrodden alien slave races how a real warrior race beats the snot out of their oppressors. Bonus points for actually being plausible about the way the Rock Beats Laser.
 * In A Good Cause... by Isaac Asimov: This comes up as a side note in story, where one character notes that the alien enemy has a larger and unified empire, as opposed to the human empires, which are smaller and fragmented. Earthlings beat them because humans are so very much better at fighting, both in terms of skill and experience, and in terms of technology, having been practicing on and competing with each other for a long time. Earth diplomacy has in fact been devoted to maintaining this edge by blocking all attempts at forming The Federation while ensuring that no human power allied with the aliens.
 * While humans are not the only warriors in the JRR Tolkien franchise they are almost always pretty good at head cracking. The first humans the elves meet are the three tribes of the Edain which arrived hacking their way through a generations long migration through Morgoth's territory. Later even Hobbits(who are a subrace of humans) get a few licks in even though they prefer not to be warriors.
 * Known Space series by Larry Niven: Humanity was almost completely pacifist at first contact. As the blurb on the Man-Kzin Wars books says, "Man had decided to study war no more because they were very, very good at it". The Kzinti fight wars of conquest, Humans fight wars of extermination. The Kzinti could easily wipe out Earth's population early on with relativistic impactors, but they prize human slaves and want to take humanity's worlds for their own. Humans have no qualms about using such weapons on their own colonies under Kzinti occupation, however. The Kzinti are horrified to discover that even unarmed human vessels are a threat.
 * Liberty's Crusade, a StarCraft novel: When Mike Liberty says that "We humans are the most ornery cusses in the galaxy" and says that the only reason humans are "getting their clocks cleaned" by the Protoss and Zerg is because we can't get along with each other. Just about every description of the Terrans in the Starcraft manuals and the official websites makes sure to point out how the Terrans' inventiveness and survivalist spirit helped them stand their ground against both the Protoss and the Zerg.
 * Mind Pool duology by Charles Sheffield: Humans are the only intelligent species that actually kills other intelligent beings. The other races consider intelligent life too sacred to harm, and are horrified nearly to the point of physical illness at the very thought of murder. This means that many of them fear humanity... but it also means that humanity is extremely useful on the occasions a hostile power makes itself known.
 * Orphanage series by Robert Buettner: The threat of nuclear war and the decaying ecology of planet Earth has focused most technological advances toward the environment, while things like space travel and warfare have absolutely zero priority. So when alien slugs start firing bullets the size of skyscrapers at highly populated areas, we're left with little more than Vietnam-era weapons and modified 747's to invade a settlement on Ganymede held by millions upon millions of hive-minded highly-advanced aliens. If you really need to ask how that turns out, you need to pay more attention to some of the other examples on this page.
 * Starship Troopers: Has basically no purpose other than to invoke this trope, as often and as hard as possible. They are, at least, fair about it; it's made clear that the Bugs are also warriors. There are other races in the galaxy too, but at least as far as narrator Juan Rico is concerned, they don't matter. The galaxy belongs to the race strong enough to claim it.
 * Technic History by Poul Anderson: "That race still bears the chromosomes of conquerors. There are still brave men in the Empire, devoted men, shrewd men ... with the experience of a history longer than ours to guide them. If they see doom before them, they'll fight like demons."—Brechdan Ironrede of Merseia
 * The Tripods : When The Masters come they decide that humans have so much dakka and so much fondness for using it that the only way to conquer humans is mind manipulation. That is a race capable of interstellar travel is afraid to fight humans face to face. However once that technique is used, Earth turns out to be fairly easily conquered, at first. Several generations later when the second wave of Masters arrives they find every Tripod city destroyed and the humans ready and waiting.
 * Troy Rising: Uses this trope, along with most of the other Humans Are Special subtropes. Not long after first contact, a top-flight alien AI spends several days crunching the numbers, and recommends that his builders - a huge, ancient, wide-spread empire of mostly-peaceful but technologically advanced traders - ally with humanity specifically for the purpose of a Type-2. The race's leaders are somewhat skeptical as to what a single, non-unified planet in the ass-end of the galaxy could possibly do, but in the end, trust in the judgment, and hands humanity some basic tools that they can use to pull a Type-1 on the Horvath that are already treating them as slaves. Sure enough, humanity soon bursts onto the galactic scene in a cloud of 'Crazy Enough to Work' and 'No Kill Like Overkill' utilization of both home-made tech and 'borrowed' Glatun technology. Even the highly-militarized Scary Dogmatic Aliens, the Rangor, are shocked at humanity's approach to warfare, with those few members of their research-groups who actually realize the threat of humanity being brushed off as doomsayers.
 * The War of the Worlds: The humans prove their warrior attitude, artillery takes out one of the tripods, and the HMS Thunderchild another two (out of a total of probably about 30). We'd probably have taken out more as well, but Mother Nature beat us to it.
 * With Friends Like These...: By Alan Dean Foster: It is told from the alien point of view, humanity was sealed under a forcefield a long time ago because we scared them that badly. When they release the humans in exchange for helping them against a bigger menace, one of the aliens has the sense to worry "What happens when we run out of enemies?".
 * Worldwar series by Harry Turtledove: While this involves an Alien Invasion, the aliens ("the Race") have been at peace on three unified worlds for thousands of years and have assembled their conquest force based on ancient plans: the recruitment of soldiers is a one-off event known as a "Soldiers' Time". They are horrified by humanity's dozens of countries and factions and the fact that, even though they are technologically more backward, they're also far better at fighting. Of course, the fact that they invaded in 1942 also helped. They spotted us during the crusades, and invaded 800 years later. To them, those centuries would have meant nothing. However to humans it was different story. Not only did we advance our technology as a whole we also changed our tactics and adapted faster. Our audacity also shocked them, such as  Their fleet commander was a little bit miffed at that.
 * One of the prevailing theories the Lizards came up with to explain our technological and social adaptability is that we're always beating the shit out of each other and always trying to find a bigger stick, while they are pretty peaceful and don't really have a reason to push their technology and society so quickly. In addition, things like poison gas, mutiny and torture are completely unknown to them because of this long-lasting peace.
 * Xeelee Sequence by Stephen Baxter: Has this in spades, at least once the Interim Coalition of Governance takes over. The titular alien Xeelee outclass them in pretty much every sphere of technology, but the Fantastic Racism of mankind's "Third Expansion" doesn't let a little thing like that stand in the way of galactic conquest. A line in Exultant expresses humanity's fighting strategy; something like: "To the Xeelee, we were little more than rats - so that's what we became. Tenacious, relentless, swarming; fighting an interstellar war with teeth and nails".

Live-Action TV
""The War. The humans, I think, knew they were doomed. Where another race would surrender to despair, the humans fought back with greater strength. They made the Minbari fight for every inch of space. In my life, I have never seen anything like it; They would weep, they would pray, they would say goodbye to their loved ones, and then throw themselves without fear or hesitation at the very face of death itself, never surrendering. No one who saw them fighting against the inevitable could help but be moved to tears by their courage. Their stubborn nobility. When they ran out of ships, they used guns, when they ran out guns they used knives and sticks and bare hands. They were magnificent. I only hope that when it is my time, I may die with half as much dignity as I saw in their eyes in the end. They did this for two years they never ran out of courage but in the end, they ran out of time.""
 * Babylon 5 :In the Backstory, humanity explodes onto the galactic stage as a major power despite their youth and comparatively primitive technology when they enter the Dilgar war and are directly responsible for ending it within a year. Their later defeats in the Minbari War were primarily due to the technological disparity between the sides, as evidenced by Londo Mollari's quote:

"O'Neill: "This... (holds up a Jaffa staff weapon) is a weapon of terror. It's made to intimidate the enemy. This... (holds up the P90) is a weapon of war. It's made to kill your enemy.""
 * Doctor Who:The Sontarans are genetically engineered super soldiers, supposedly the finest in the galaxy (and about 4' 10") with highly advanced technology. Once UNIT get around the technology that was jamming their guns (since it affected the bullets, they changed bullets), their speed, mobility and high rates of fire let them to go through the Sontarans like a hot knife through melting butter. Given their tendency to be a Redshirt Army, it was... cathartic.
 * Dalek Sec, upon merging with a human, outright states that humanity 'has such a wonderful mind for war', and that they are the great survivors of the universe (since human's establish a series of interplanetary empires and are one of three species that still live at the end of the universe, he had a point).
 * Stargate SG-1: Many Goa'uld and Jaffa have learned that the Warriors of the Tau'ri epitomize the "Humans are Soldiers" variation of this trope. For all their advanced technology, the Goa'uld are the equivalent of a semi-competent Third World army: very capable when it comes to killing peasants and fighting each other, but ultimately hopeless against the modern, disciplined military organizations of Earth. Lampshaded in one episode where O'Neill compares human weapons to Jaffa weapons.

""Let me tell you something about Hew-mons, nephew. They're a wonderful, friendly people - as long as their bellies are full and their holosuites are working. But take away their creature comforts... deprive them of food, sleep, sonic showers... put their lives in jeopardy over an extended period of time... and those same friendly, intelligent, wonderful people will become as nasty and violent as the most bloodthirsty Klingon. You don't believe me? Look at those faces, look at their eyes...""
 * Star Trek: Deep Space Nine: The humans were some of the bitterest fighters against the Dominion. Quark puts it best in The Siege of AR-558:


 * Though Klingons sometimes mock and condescend to humans, they have always respected our battle prowess. We were one of the few species to give the entire Empire serious trouble for much of their recorded history - enough that they eventually found it better to ally with us. Later on, it's taken Up to Eleven: When the Klingon chancellor is murdered through dishonorable methods, the Klingon Empire puts the matter of their Rite of Succession in the hands of none other than Jean-Luc Picard, specifically because of humanity's honor and courage in battle.
 * Klingons only originally allied with the Federation out of desperation; their homeworld was dying (a major plot component of Star Trek VI). However, as shown in the TNG episode "Yesterday's Enterprise", the fact that a Federation Starship flew headfirst into battle outnumbered by Romulans to save a Klingon outpost strengthened this alliance, and, as the events of the alternate timeline indicate, indeed saved it.

Tabletop Games

 * Banestorm: Humans arrived on the world of Yrth when the Banestorm, conjured up by elves to remove orcs from their world, malfunction. Within a few generations they Take Over the World and their only real enemy is each other.
 * Mekton: Back story for the Invasion Terra setting has this with a few traces of type 2. The Human Alien invaders have all the edges: longer-established technology, the ability to clone armies in a month, FTL... But we have a few of our own, stuff like "Human Adaptability", "Stolen Mecha Technology", "Guerrilla Warfare" and a few of their friends. At one point, they're caught flat-footed by humanity switching over to AM radio because they can tap into our FM signals. The "Type 2" part also shows up: their obsession with honour means that they don't know what to make of guerilla warfare. Towards the end of the storyline, they have not only been thrown off Earth, but have to divert entire fleets to hunt Terran raiding ships. The take-home message? Do not fuck with planet Earth.
 * Traveller : There are a multiplicity of human cultures. Almost all of them know how to handle themselves in a fight pretty well, and some highly emphasize that aspect of their culture. Moreover the main method of organizing military forces is based on the typical one found on Ancient Terra.
 * Warhammer 40,000 The average humans’ equipment and physical abilities are generally less than other species'. This is not usually good for morale but, humanity is united under The God Emperor of Mankind, founder of the Imperium of Man. The empire has millions of planets to its name and many more citizens. Humanity survives by fielding a massive military machine that recruits from entire planets, creates armies of Super Soldiers, and makes ships large enough to be cities in their own right. Humanity is more than willing to use extreme force against the various aliens and demons they encounter in the galaxy.
 * The Tau initially saw humans as a subversion of this seeing their warriors as badly trained, poorly motivated and badly equipped. However they then realised that the forces they had been fighting so far were planetary defence troops (who are regarded in universe as being pretty pathetic even by the guard (the guys with flack vests and torches....)) and those troops that could be spared from the more pressing concern of fighting the all consuming tyranids. It was also about this time that they realised that the Imperium, rather then being an empire of similar size to them, dwarfed them by several orders of magnitude. In 'Kill Team' one of the characters tells a Tau diplomat that he's from a small hive world with a population of something like 10-15 billion, the Tau diplomat is described as being somewhat agitated to find out that this is not exceptional. And of course shortly after this they met the space marines.....

Video Games

 * Command & Conquer 3: Tiberium Wars has many examples of this.
 * A quote from the Scrin Intel Database: "... Indigenous population warlike to the extreme - once Threshold construction is complete and gateway is open, entire indigenous population must be cleansed from the surface of the planet."
 * Deadlock: Has the Skirineen, a race of merchants without a conscience. When the now-peaceful and seemingly harmless humans refuse to trade with them on their terms, the Skirineen try to force their hand and blow up the moon to show they mean business. Instead, humanity reveals its violent roots, rearms and curbstomps the Skirineen.
 * Halo game series: The humans' tendency toward courage, tenacity, and innovation is the only thing keeping them from falling to the technologically superior Covenant. It is also one of the main things that endear the Sangheili of the Covenant to humanity allowing for a later alliance.
 * After the war, the Sangheili are having an extremely difficult time adapting their society to complete jobs normally reserved for other species in the Covenant; since their whole populace is indoctrinated with the belief they are worthless if they are not warriors. One makes a comment in the Glasslands book that humans do not excel at anything, but are able to get by because they are simply good enough at everything.
 * In the new Forerunner series, it is revealed that
 * ''Mass Effect':' Humans are of the average mold with particular people filling in the special part, but this trope is regularly very important. Humanity shows a surprising amount of combat prowess against the Turian fleet they encountered in the Contact War causing the mobilization of the entire Turian military. Humanity has repeatedly shown an aggressive and war like attitude, rapidly gaining a reputation as tenacious fighters. In addition Humuanity frequently establishes colonies in various hostile reaches of space. They have to frequently fight to protect their territory and colonies from various raiders and threats.
 * According to the back-story Humans also use entirely different military tactics. Humans pretty much introduced the concept of a carrier to the galaxy. Also, most of the other species station a few ships at each inhabited planet to try and protect them all. The back-story says humanity leaves a large number of ships at a central place a few hours from all of the planets they control. Humans with the aide of Turian engineers design a new type of stealth ship, blending stealth and firepower into one package. The ship is both a warship and a covert operations ship. It is considered one of the most advanced ship designs in the galaxy.
 * When Mordin's team was doing their research and modeling for the effects of the Krogans’ adaptation to the genophage, they predicted (based on millions of data points and countless scenarios) the only outcome of the adaptation was war and galactic expansion. A galactic expansion that the models showed would have been stopped by the Turians and the Humans. The fact that the Salarian models pretty much said that the humans would provide as much military effectiveness as the Turians, the most militarily powerful species in Citadel space.
 * Super Robot Wars: It is the main reason of multiple Alien Invasions in the Original Generation timeline. It is even lampshaded many times in the game.
 * Sword of the Stars': In the backstory humans are healthily respected, if not exactly feared, by both the Tarka and the Hivers for their ability to grow into a galactic power at record speed. We did this after our only planet was nearly bombed to rubble by a rogue Hiver clan. We then expanded and colonized other worlds while at war with parts of both races (neither have an entirely unified government) who had a couple of millennia worth of head-start.
 * The hivers arrived over a pacifist Earth just in time to kill the first human starship ever, and proceeded to be driven out of the system by a species that had no space military.
 * Urban Assault: The planet has been invaded by Mykonians and Sulgogar. One of the briefings states that, if the humans had banded together instead of splintering into different factions, they'd have won already. Among the human factions, special mention goes to the Taerkasten, for having the most resilient units in the game despite using technology from WWII.

Web Comics

 * Vexxarr: Touched on in this strip. These sneaky bastards have regular exercises to keep their mobilisation potential high, you see.
 * Though the Mahakalosians disagree with that classification.

Western Animation

 * Galaxy Rangers:Some of column A and some of column B were implied but mostly the latter, as the Andorians and Kiwi were actually pretty decent. The Andorians and Kiwi have fought off The Empire, led by The Queen of the Crowns. They "journeyed to Earth, seeking our help," but the Kiwi are more farmers than fighters (not that they can't if you push them), and the Andorians' hat is that of mathematicians and scientists unless you jail them. There is still the genocidal meglomaniac who is none too pleased to have defections from her Empire and two species who need an ally who's good in a fight. Hence the reason they send Zozo, Waldo, and a hyperdrive design that's miles ahead of anything the Queen has to essentially bribe Earth into an alliance. While Kirwin defends itself with a planetary defense shield, Earth is shown to be just plain armed to the teeth. It's also worth noting that while the series had Loads and Loads of Characters, virtually all the military were humans.

Anime and Manga

 * Guyver: humans were engineered as warriors by a race known as Uranus. Then they decided to see what would happen if they gave a human one of their standard-issue suits of organic Powered Armor—the result was the human becoming absurdly powerful and breaking free from their Mind Control. They eventually managed to kill him, but they were so terrified of it happening again that they aborted the experiment and fled the planet.

Comic Books

 * Grease Monkey graphic novel: Humanity (along with uplifted gorillas) are recruited as warriors to face an alien horde.

Film
"Gabriel has a plan. Humans, and how I love you talking monkeys for this, know more about war and treachery of the spirit than any angel. Gabriel is well aware of this, and has found a way to steal the blackest soul on Earth to fight for him."
 * The Prophecy: Provides a dark example where rogue archangel Gabriel attempts to steal the soul of a utterly psychotic Complete Monster of an army officer to aid him in his battle against the angels who have stayed loyal to God. As Satan sums it up:


 * Transformers Film Series: Humans and the Autobots playing out this trope.
 * Humans have technology just advanced enough to hurt the Transformers, numbers, and the fact that they're fighting on our home turf. Of course, the Transformers are far from pacifists, having been locked in a civil war for millions of years, (according to the Transformers Wiki, they consider one upside of our short lifespans being that our wars are mercifully short)

Literature
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 * Animorphs: The Yeerks see humans as a powerful race because we're weak. However, despite the fact that Earth is a Death World to our species, we have emerged as the dominant species. This would make for great shock troops and since we reproduce in great numbers, the Yeerks couldn't resist.
 * Berserker series by Fred Saberhagen: The Carmpan, being pacifists, were unable to confront the Berserker threat directly. Instead they found a weapon: Humans.
 * The Course of Empire and The Crucible of Empire. The Jao admit that the humans gave them the hardest fight of all the races they conquered(and anyway they only conquered the humans by being willing to throw asteroids at Earth while humans weren't willing to use nuclear weapons; a thing Jao, don't admit). Because of the humans skill at arms the Jao give them favored status in their empire
 * The Damned trilogy by Alan Dean Foster: Is a classic example with a coalition of pacifistic aliens who have been fighting a centuries-long losing battle against a race of fanatical, mindwashing conquerors moved by a mysterious spiritual/religious principle. The problem is that every race is so civilized, few can even conceive of hurting another sentient, and even those who aren't quite that civilized and try to do whatever fighting is necessary aren't really any good at it. Then the coalition finds humans, a race ripe with contradictions but whose fighting abilities are beyond anything anyone, friend or enemy, has ever seen. In fact, humans can be so unpredictably and barbarically violent that the coalition would prefer to not use humanity at all, and only relents because if the enemy gets to them first the war is essentially over. A lot of curb-stomping ensues.
 * An amusing moment in the first book is when one group of aliens field-tested a group of human 'warriors' against enemy forces, and were highly impressed by how the 'elite' humans rapidly defeated the opposition, in a performance comparable to the aliens' very best soldiers. Later on in the series we found out that the humans in question were a bunch of untrained civilians randomly grabbed off the street and the same aliens are watching in absolute horror as Special Operations Command is doing its thing, which to the alien POV is a level of calculated violence orders of magnitude beyond their worst nightmares.
 * The Excalibur Alternative by David Weber: Another alien picks up a medieval English army for use as muscle for his extortion racket. The rules of galactic society allow trade with undeveloped planets and even the use of coercion to get them to agree, but use of advanced weapons (gunpowder and up) is prohibited. One of the alien's competitors picked up a Roman legion a thousand years ago and has been using them to "renegotiate" contracts ever since. So another alien wanted to get in on the action.
 * Ganymede series by James P. Hogan: The Giants evolved in an ecosystem completely devoid of predators and are instinctively pacifistic, to the point that they have no real concept of "war". They also recognize that humans' warrior abilities (and our understanding of violence and duplicity that comes from being warriors) is all that saved the Giants from being destroyed.
 * Humanx Commonwealth series by Alan Dean Foster: When the insectoid thranx first met humans, both were battling a third species: the incurably antagonistic AAnn. As the Enemy Mine relationship forced the two species closer together, psychological research unveiled some truths that each considered ugly about themselves. When stripped of their inhibitions, humans become berserkers; when thranx are treated likewise, they become cold and efficient calculators. The two psyches combined form a frighteningly efficient combat team, which is utilized to pilot small, two-person stingships against the AAnn to deadly effect.
 * The Last Starfighter by Alan Dean Foster: Used to explain why the Star League is so hard up for fighter pilots as to be recruiting them from pre-contact worlds. Most Starfighters are, by the League's standards, homicidal maniacs. Just hearing the battlecry "Victory or death!" made a visiting official physically ill.
 * It is also mentioned that the official giving the speech that ends with him starting the "Victory or death!" chant had to be almost out of his head on tranquilizers to go up and make use of such violent rhetoric, and even then he was only barely able to hold it together. Mind you, he was the Big Bad's father, and the shared genes made him the only politician capable of giving the speech at all.
 * Pandora's Planet : A very successful, if slightly dim, race of Outer Space Imperialists conquer the Earth with considerable difficulty, then are quickly and hopelessly subverted by the joys of human civilization; food fads, rock and roll, and planned obsolescence.
 * The first couple chapters are about the aliens discovering that humans are better at fighting and the rest describes various campaigns by human mercenaries on behalf of the aliens.
 * Posleen War Series by John Ringo :The pacifist alien races aren't quite that ridiculously pacifistic, but they still wouldn't survive long without humans to fight their battles for them. (They're also ) More specifically, each race has its own flavor of pacifism. The Indowy have no moral objection to violence, but as a race are too anxious to go into battle. The Himmitt evolved with chameleon-like body camouflage and thus are culturally biased to stealth over combat. The Darhel were genetically engineered to have violent desires, but also to become comatose if they ever indulge those desires.
 * Ranks of Bronze by David Drake: Unscrupulous alien merchants are required by galactic law to use contemporary technology to wage war on primitives, so they keep a Roman legion on hand to wipe out any pesky upstarts with bladed weapons. The Romans self-identify as the Humans Are Soldiers variant: they are soldiers, not warriors, and that is how they can consistently win against opponents with roughly similar technology.
 * Target by Janet Morris and David Drake : Features an alien diplomat from a pacifist civilization who arrives on a Lunar Base fleeing more violent aliens. After the humans defeat several of the alien soldiers, the pacifist alien decides to present humans as "their" warriors in order to negotiate a peace treaty.
 * Confederation of Valor series by Tanya Huff: A federation of hyper-pacifist aliens comes under attack by another group of aliens. To counteract this they recruit less advanced and therefore more warlike aliens to fight for them in exchange for technology. This includes humans, of course.

Live-Action TV

 * Babylon 5: The Vorlons
 * Doctor Who serial "The War Games":The Big Bad the Warlord is recruiting his warriors from conflicts in Earths past because of humanitys’ talent for war.
 * Earth: Final Conflict : The Taelons in say they've come to Earth to be our friends, but actually want us to fight their wars for them.
 * Farscape: In the back story  What is notable about the Peacekeepers is the complexity of their characterization: individuals, especially higher-class officers and commanders, vary from Complete Monsters to Well Intentioned Extremists, but the rank-and-file Peacekeepers, aside from their ingrained xenophobia, are an example of a proud soldier race, and in the miniseries, while working with the heroes to fight the galaxy-conquering Scarrans, actually come off as heroic.
 * In Stargate SG-1 the Tau'ri's relationship with the Asgard is this. The Asgard ask for our help after the Replicators destroy most of their empire and their race. The Asgard's fatal mistake with the technology-assimilating Replicators was making more sophisticated and high-tech designs to counter them, which the Replicators simply absorbed and turned against the Asgard, rendering them largely immune to energy weapons. However, solid projectile weapons are so low-tech the Replicators had nothing to counter with. The Asgard then asked us to help them destroy the Replicators since we were "stupid enough" to defeat them. In turn, the Asgard become one of SG-1's most important alien allies.

Tabletop Games

 * GURPS: Time Travel sample campaign Eternity's Rangers, in which some mysterious Sufficiently Advanced Aliens acquire soldiers from all through history just before they were "supposed to" die and make a commando team to go throughout time on missions for unknown reasons.

Video Games

 * Galactic Civilizations: While humanitys’ hat appears to be diplomacy, they have been killing each other for over nine thousand years and they have gotten very good at this. The Drengin are the only aliens who realize this and it scares the shit out of them.
 * There was some official Backstory for GalCiv that described how humans defended an unnamed race that the Drengin had been picking on for so long that the rest of the galaxy didn't care. Before that conflict humanity was seen as a generally harmless race of facilitators, diplomats, and traders. After that conflict, the major galactic races realized that while humanity always prefers to offer a velet-gloved hand of peace to others, underneath that glove is a a very heavy gauntlet.
 * In fact, this is why the Drengin, the mightiest warrior race in the universe, fear humanity. They thought that humanity was weak, noting that they didn't even have a standing space fleet. Then the Xendar attacked a human colony. Not even a major planet, just a minor colony. The humans mobilized immediately and within a year had completely eradicated the Xendar race. Not just defeated, wiped out. To quote: "There are no more Xendar. They're gone. Completely." Then humanity disbanded the fleet and went right back to being "peaceful". On seeing this, the Drengin promptly crapped themselves and raised mankind's threat level from "nonexistent" to "extreme".
 * Half Life: One of the things The Combine want with the human race for. Humans seem to be the only one of the races (at least out of those we've been introduced to) that manage to fight back against Combine control.
 * It is worth noting that the Combine occupation force consists almost entirely of humans who haven't been completely assimilated yet and the real Combine military managed to crush the human race within seven hours.
 * Nexus: The Jupiter Incident: The Vardrag become patrons of the Noah colony a lost human group. They trade technology and assistance for human war making skill since they lack the "stomach" for war themselves.
 * Star Control games: According to the back-story of the games humanity becomes pacifist after a "small" thermonuclear war in 2015 scares us straight. A century later we are befriended by benevolent aliens caught in an interstellar war. They are delighted to learn that we still have a huge arsenal of nuclear weapons locked away in storage, apparently along with the skills to become competent and effective warriors once more. It is noted that Humanity makes a surprisingly useful contribution in the war against the evil Ur-Quan, considering our relative lack of technological advancement. It still doesn't end well. Afterwards, the Ur-Quan feel the need to not only encase Earth in an impenetrable shield, but also station an entire fleet on the Moon just to make sure we don't try anything "sneaky."
 * The Yehat, a species of honor based warriors, who look like pterosaurs and have a feudal, clan-based society, actually respect the humans a lot because we have one important thing in common. Both of our civilizations developed many of their major technologies through conflict. So for them, we are a warrior race too.
 * Lest it be forgotten, there were humans on both sides of the Hierarchy-Alliance War: the Androsynth were, after all, humans who happened to be the product of cloning. And the Androsynth Guardian was definitely one of the tougher Hierarchy ships.
 * Super Robot Wars: The Balmarians want to conquer Earth to turn the population into soldiers.
 * Tabula Rasa Gives this as the reason why good aliens gave humans wormhole technology. The humans in turn help them fight their long term enemies who also happen to invade Earth.
 * The Boron Campaign in the backstory of the X-Universe featured the pacifist Boron being attacked by the Split. The Boron were losing badly, of course. The Argon, a civilization descended from a human warfleet that trapped itself in deep space to lure insane terraforming drones away from Earth, took pity on the Boron (partly because they themselves needed an ally against the Paranid) and gave the Split a Superweapon Surprise.

Real Life

 * The majority of Real Life UFO lore tends to imply this. The Greys are depicted as genetics experts who are nearing extinction, needed our genetic material in order to restore their own reproductive capabilities, and because they knew what warlike fuckers we supposedly are, agreed with the Eisenhower administration to trade us weapons and propulsion technology, in exchange for the right to abduct members of the population, to get what they needed.
 * A further implication is that whenever positive/benevolent extraterrestrials show up within our airspace, they can generally expect to be shot down with the particle beam weapons supposedly given us by the Greys, and then for us to incarcerate and torture them in order to obtain more weapons tech. The consequence of this, is that among positive extraterrestrials, Earth supposedly has the general reputation of one of the worst places to be in the known universe, which in turn is cited as the reason why the proverbial public White House lawn landing hasn't happened yet, because the extraterrestrials know what they'd get if they tried it.

Tabletop Games

 * BattleTech: The Inner Sphere successor states have been fighting a war of attrition against each other for hundreds of years after the fall of the Star League. Along comes the self-exiled remnants of the Star League's own forces, the Clans. After the initial shock of the Clans' superior technology and individual mech pilots wears off, the Inner Sphere forces (at this point more or less united against a new common threat) learn that the Clans' rather strict ritualized honorable combat is strategically and tactically exploitable. In this case, both sides are "Human" more or less. Having more experience in total warfare instead of just ritualized duels, they eventually halt the Clans' advance and even render their entire invasion null by their own honor system (after wiping out a clan that was particularly brutal during the invasion). The clans that deal more with the Inner Sphere states have since adapted a more flexible and emulative doctrine against them, but the Inner Sphere is still better at it.