Divided We Fall

""We must, indeed, all hang together, or assuredly we shall all hang separately.""

- Benjamin Franklin

The Evil Overlord is about to conquer the country, and The Rival is more concerned about his personal feud with the hero. He may not realize the danger. He often disbelieved either because of his resentment, or honestly, not trusting The Hero. But the damage is real even so.

Malicious Slander often fans the fire. The Rival may perpetrate it—or just be extremely gullible, blinded by his dislike for The Hero. Can also be egged on by Divide and Conquer tactics by the real enemy.

Heroic counterpart of Enemy Civil War—though, obviously, at least The Rival is not usually very heroic. Enlivens the life of many a hero, though.

The better sort of rival will come to his senses with the enemy actually at the gate, but not without doing heavy damage to the cause first. However, often, Redemption Equals Death. Not always. Sometimes, at that, The Hero learns An Aesop about how people can legitimately suspect him without being evil. Either way, Teeth-Clenched Teamwork is likely to ensue—though that may lead to Fire Forged Friendship and prevent reoccurrence. The Leader can sometimes resolve it earlier by trampling objections.

The worse sort may actually become the Turncoat, undergoing a Face Heel Turn. This shifts them out of the ambit of this trope. Obstructive Bureaucrat and The Resenter frequently cause this.

Contrast With Friends Like These...; this has deadly serious effects, and also can be carried out with perfect courtesy all around. Contrast Sour Supporter, who will work for you, but just to let you know, he thinks you're insane. When The Hero and The Rival work for different organizations, Interservice Rivalry may be involved. Supertrope of We ARE Struggling Together! and A House Divided. See also Ignored Enemy, Rebellious Rebel, Headbutting Heroes, ...Who Needs Enemies? and Not-So-Omniscient Council of Bickering.

Anime & Manga

 * In Shakugan no Shana, the Flame Hazes tend to be lone wolf types and apparently it's unusual for Flame Hazes to ever work together, even though they have the same goals; Margery Daw is hostile when first encountered (she wanted to kill the one particular Tomogara who isn't harmful). Later, when Wilhelmina shows up, she conflicts with Shana, who has decided to save the world without killing Yuji.
 * Neon Genesis Evangelion, NERV is fighting to save the world the world from complete destruction, yet the UN keeps cutting its defence budget, heck it even wanted to Nuke Tokyo 3 into oblivion if the situation looks bleak. Might even be deliberate, seeing as after the Angels are destroyed,
 * Somewhat justified in the fact that over the course of the series, Tokoyo-3 and the evas take an ernomous amount of damage, and NERV's infastructure is incredibly expensive just to begin with (Massive rifles for the Evas to use? Experimental particle beam weapons? That crap's not cheap). It's also implied that the economy of the post-2nd impact world is much worse then ours, particularly if doing your laundry and buying steak dinners is "expensive".
 * Cruel irony.
 * Thanks to an elaborate Xanatos Gambit by the villain of the School Festival arc in Mahou Sensei Negima, lead Negi was being held responsible for The Unmasqued World, with his True Companions being hunted as accomplices. This had the re-grouped friends fighting far better-trained mage teachers and students employed by the school is guards with Negi taken prisoner. They ultimately succeeded in rescuing the lead, though not without tremendous hinderance and generally having life made a little harder.
 * Lelouch and Suzaku want to make the world better. They also happen to be best friends. Unfortunately, they repeatedly screw each other over without realizing it until the point where they both look like hypocritical, dog kicking jerkasses. Eventually
 * Also, the Black Knights leaving the JLF to die. Nightmare of Nunnally takes this one step further into Zero and Kyoto flatly selling them out. They were too unpredictable.
 * At least twice in Dragon Ball Z, Vegeta would deliberately allow the Universe-Destroying Abomination Of The Week to power up so he could have a "worthy" opponent to fight—even going as far as to battle his own allies to let it happen. First, he did it in the Cell Saga, where he stood back while Cell attained his "Perfect" body, then battled Trunks, his own son, when the latter tried to stop it. In a later arc, when he and the other Z fighters raced to avoid the awakening of Majin Buu, he let the magician Babi Di empower him with a malevolent sigil, and forced Goku to battle him instead of helping save the world. Gohan and the Kaio-Shin were left to try to stop Buu on their own. Naturally, they failed, since Buu absorbed the Battle Aura shed by Vegeta and Goku in their duel.
 * Averted in Death Note: while Mello and Near start out as enemies (at least, from Mello's perspective), and when Mello visits the SPK headquarters he uses a hostage and is held at gunpoint, but instead gives him a vital- if cryptic- piece of information about Kira.
 * Cosmo Entelechia and Ala Alba are both trying to save the magic world in Mahou Sensei Negima. The problem is that the former doesn't believe in the latter's plan, which has a more optimistic solution. Which is honestly justified considering the situation and who is informing them of it.

Comic Books

 * Extremely common in superhero comics, as many writers look for any excuse to have heroes fight each other. As a specific example, the official superteams of countries America is less than friendly with, like Marvels (former) Soviet Super Soldiers/Supreme Soviets/People's Protectorate/Winter Guard and DC's Big Ten (China's national super team) are always - ALWAYS - more interested in keeping American hero teams out of their home countries than they are in teaming up to stop the rampaging monster/villain/aliens/whatever that the American heroes have chased across their border.
 * That said, the People's Protectorate and the Avengers make for a pretty good team when they stop squabbling.

Film

 * High Noon. Kane's deputy refuses to help him unless Kane agrees to the deputy becoming his successor.
 * In 1776, as well as in real life, Benjamin Franklin says "If we do not hang together, we shall most assuredly hang separately!" Also, until Richard Henry Lee brings Virginia's approval to debate the idea of independence, most of the congressmen refuse to second John Adams' proposal to debate independence. John Dickinson never stops supporting the crown however, even after his cause is lost, although that is not out of pure animosity towards Adams.

Literature

 * In David Wingrove's Chung Kuo series: the Ping Tiao rebels, the Yu rebels, the businessmen in Europe and later the businessmen in North America, and of course Howard deVore's operations
 * From Dan Abnett's Warhammer 40000 novels:
 * The Gaunts Ghosts novel First & Only is driven by two rivalries: between the Ghosts and the Jantine Patricians, and between Dravere and Macroth. Indeed, the first rivalry, and its Revenge, is used to cover up other intrigues—and this in the face of the forces of Chaos!
 * In Ghostmaker, they have another rivalry between the Ghosts and the Volpone Bluebloods. While the Bluebloods themselves are not all evil, their commanders once wittingly bombarded where they knew the Ghosts were, and at the climax, two officers are in a brawl until a Chaos beast actually erupts on them, killing several of their troopers.
 * In Traitor General, blamed his fall on Gaunt's unwillingness to let the past go and jockeying for power.
 * And of course there's Admittedly this was because.
 * In his Inquisitor series—both Eisenhorn and Ravenor—the inquisitors in question spend as much time resisting the Inquisition as they do the forces of Chaos.
 * In Brothers of the Snake, a Space Marine Khiron shot and killed another after a fight with Chaos forces. When another Marine, Priad, finds it hard to believe that he just murdered him and investigates, the squad of the dead Marine corner Priad in an attempt to intimidate him out of dishonoring them.
 * In Titanicus, a member of Adeptus Mechanicus reveals a purported proof that the Omnissiah and the Emperor are not one and the same. This results in rupture with the order and with the Imperial forces -- while the planet is being invaded.
 * In the Horus Heresy novel Legion, Namatjira learns that the Alpha Legion is operating on a planet he is trying to bring into compliance. When his subordinates speak of a lack of respect, Namatjira complains that it makes strategy impossible, because he does not know what his forces will be doing.
 * In Sandy Mitchell's Ciaphas Cain novel The Traitor's Hand, when Cain is trying to stop a daemon-summoning, Rival Comissar Tomas Beije tries to arrest him. Only by deploying Kill Me Now or Forever Stay Your Hand does Cain succeeding in getting to the summoning.
 * Cain also exploits this trope in the same novel by following a rival band of Chaos Space Marines into the facility and allowing them to do most of the work of clearing the defenses between him and the summoning, all the while trying not to provoke them himself.
 * In Cain's Last Stand, Cain acts to forestall this between Adeptus Mechanicus and the Inquisition. When they are disputing who is responsible for the Chaos forces knowing of a relic, Cain puts the blame on a rogue Inquisitor that caused them some problems years earlier -- not knowing whether it's true, but wanting them focused on the forces.
 * In the Codex Alera series, as the extremely deadly and its millions of minions, execute many Curb-Stomp Battles on the Alerans, the First Lord realizes this trope will be true unless the Alerans forge alliances with all of their long-time enemies.
 * The Honor Harrington series had one of these on the Haven side - in War of Honor, one character (the Havenite Secretary of State) is sabotaging diplomatic communications to engineer a crisis that he can ride to the Presidency. His predictions of how everyone will react to the altered communications, particularly the person he wants to replace, are proven drastically wrong.
 * In Terry Pratchett's Discworld novel Night Watch Ned Coates fits this trope, at least in the scene where
 * In William King's Warhammer 40000 Space Wolf novel Grey Hunters, Trainor recounts the infighting between the separate factions on Gram. Among the Space Wolves themselves, political conflict is enough to make Ragnar think of this, though it does not actually affect their ability to fight (to be just to Ragnar, yes; to fight, no). And when Ragnar has retrieved Trainor and his men, the Inquisition tries to keep them as prisoners; the Space Wolves refuse.
 * Wolfblade opens with Ragnar being sent to Terra to protect him from those who blame him for, who are partly motivated by rivalry within the Chapter. And on Terra, he finds himself in the thick of the rivalry of Navigator Houses.
 * In Lee Lightner's Sons of Fenris, Ragnar recognizes Dark Angels and reflects on their Chapters' long hostility. The Dark Angels and Space Wolves fight. Later, Abandoned By the Cavalry occurs
 * In Graham McNeill's Warhammer 40000 Ultramarines novel Nightbringer, the cartels are deep in in-fighting, despite Dark Eldar Pirate raids and bomb-setting Cults.
 * In The Killing Ground, Uriel is enraged at the prospect of dying at the hands of a man whom they should fight beside and roars at him to kill him and be done.
 * In Graham McNeill's Warhammer 40000 novel Storm of Iron, the Warsmith deliberately cultivates rivalries in his underlings (using such things as Honsou's Halfbreed status), in order to spur them to greater heights.
 * Conversely, on the Imperial side, the Space Marine captain sees great bitterness and division in a briefing meeting (partly fueled by a grievous failure on the part of some forces), and demonstrates with the sticks that can't be broken the danger of this. He cites their slogans and how they obviously pertain, and the quarreling factions reconcile.
 * In Ben Counter's Warhammer 40000 Horus Heresy novel Galaxy in Flames,, envious, complains that gives him orders, while they are under attack . Which attitude leads to.
 * In James Swallow's The Flight of the Eisenstein, Decius quarrels with Garro
 * In Mike Lee's Fallen Angels, when they have found Chaos, the anger as they quarrel over how to deal with it and who is to blame is so plapable that Zahariel interposes himself between two Dark Angels. Later, Zahariel finds that the rebel forces are also quarreling among themselves.
 * In James Swallow's Warhammer 40000 Blood Angels novel Deus Sanguinius, at the climax, a Blood Angel explicitly declares that another Blood Angel ship is more of a danger than a Chaos ship.
 * In Red Fury, Ajir is bitterly resentful of two "penitent" Blood Angels allowed to join their squad. And the Flesh Tearers snipe at the Blood Angels, going so far as to fire on a location where they know they are—although they know they will survive, they also know they will be caught in the rubble. And one refuses to let Rafen speak to the Chapter Master until Rafen insists on being respected. While he does agree to come, he openly admits to the other Flesh Tearers that he is looking for something in the Blood Angels' weaknesses that he can exploit. (Along with making his resentment manifest.) And he orders a Flesh Tearer to pick a fight with a Blood Angel, to test them.
 * In Black Tide, Noxx quarrels with Rafen about who should be in command.
 * In A Song of Ice and Fire, a civil war begins while a supernatural army is about to invade.
 * In Jim Butcher's The Dresden Files, a chronic problem for the White Council. Perhaps particularly acute in Turn Coat.
 * Understandable, in some ways, though; it's extremely obvious that there's at least one traitor on the Council, and.
 * Changes hints that at least some of the bickering is fabricated to cover for the real plans.
 * In Nick Kyme's novel for Warhammer 40000 Salamander, although the Marines Malevolent have played The Cavalry, and they and the Salamanders are still on enemy territory, tension and sniping arise almost immediately on their meeting.
 * The Marines Malevolent are colossal Jerkass loose cannons even by Warhammer 40,000 standards, and almost everything they do results in this. Nobody likes them, especially not the Salamanders, who are as close to "nice" as Space Marines get.
 * Tsu'gan, dissatified with the new captain, foments discord in the company.
 * In JRR Tolkien's The Silmarillion: Fëanor and his sons repeatedly turn against their own allies in the war they are trying to wage against Morgoth. All the Free Peoples (elves, dwarfs, men, hobbits, ents) indulge in We ARE Struggling Together! instead of focusing in defeat The Lord of the Rings.
 * In Harry Potter and The Order of The Phoenix, the Ministry of Magic seems to do nothing else.
 * In this case, the difficulty can be traced to the rivalry that Fudge believes exists between him and Dumbledore. Having successfully defeated Grindelwald and opposed Voldemort before, were the Dark Lord to return again then Dumbledore would be the one people followed. With prompting from Lucius, Fudge happily buried his head in the sand.
 * In Norman Juster's The Phantom Tollbooth, the two kings know that bringing back the princesses Rhyme and Reason is what is really needed, but they'd rather disagree with each other.
 * In David Brin's Startide Rising, the fleets of aliens hunting them does not prevent fierce infighting among the dolphin crew. (Fortunately, the aliens don't get along with each other, either.)
 * In The King Must Die, a bull-jumper is killed because his team does not help him, which would create some risk for them. Theseus points out to his team-mates how defeated the survivors look, and how certain they are to die, before having them take again The Promise that they will consider each other's lives as valuable as their own. Keeping it lets them outlive the rest, and indeed, other teams take the same oath and start to live longer, in imitation.
 * A chronic problem in the Codex Alera, to the point where the Alerans are so busy fighting amongst themselves that threats like the army of 60,000 Canim that landed on the coast or wind up taking a back seat in many people's minds (especially the Senators) to personal feuds and scrabbling for power. This gets to the point where, in the last book, Senator Valerian is trying to accuse Bernard of treason for fortifying the Calderon Valley (even though ) and saying Doroga is an untrustworthy savage. So Lord Placida picks him up and throws him bodily out of the meeting.
 * The Wheel of Time is filled with those : Elaida, the Whitecloaks, the Seanchan, Andoran Houses contesting Elayne's claim to the throne, the Shaido, Carhienin and Tairen rebels...
 * Variants of this are all over Battle Royale, and in the novel
 * This trope is brought up in Star Trek: Destiny, though it's ultimately averted in one instance. As the Klingon Empire faces a massive Borg invasion, Martok's nemesis Councillor Kopek agrees this is no time for politics. When Martok, leading the Klingon fleet, calls Kopek back on Qo'noS to warn him of impending Borg attack, Kopek assures Martok his throne will be waiting for him upon his return. Martok replies "with you sitting in it, I imagine?" However, Kopek for once isn't planning anything, and says so. It's the first time the character has been presented as anything other than a selfish Complete Monster; he understands the severity of the situation. He also dies defending Qo'noS, so possibly Redemption Equals Death.
 * In Aaron Allston's Galatea in 2-D, Donna and Roger quarrel bitterly, insulting each other, while in hiding in the hotel. Donna stalks off.
 * In Shanna Swendson's Once Upon Stilettos, they discover someone was at Owen's desk and hunt for The Mole. It may even be an operation to get them all Hanging Separately, they realize.
 * In Andy Hoare's White Scars novel Hunt for Voldorius, La Résistance splits over an assassination attempt.
 * Later, after they manage to avoid a friendly fire incident—barely—the Raven Guard and White Scars snipe at each other with accusations of Glory Hound and sneeking about.
 * In Robert E. Howard's "Shadows in The Moonlight" the pirates after they capture Conan the Barbarian.
 * In L. Jagi Lamplighter's Prospero's Daughter trilogy, Prospero's children were not getting along well even before the story starts. And their enemies go to foment dissession.
 * In Robert E. Howard's Kull/Bran Mak Morn story Kings of the Night, Bran is about to lose a tribe because they want a leader of their own blood.
 * In Adrian Tchaikovsky's Shadows of the Apt, a continually problem among the countries the Wasps are conquering one by one.
 * In Jack Campbell's The Lost Fleet, a pervasive problem.

Live-Action TV

 * This happens frequently in 24, usually in the form of an Obstructive Bureaucrat who doesn't understand that Jack Bauer is always right. Jack is often arrested or otherwise delayed by a new CTU director who generally gets in the way for the first few episodes after his introduction.
 * Maybourne and the NID do this a little in the first few seasons of Stargate SG-1. Particularly the episode "Politics," in which Daniel knows that the Goa'uld will attack Earth, and no one outside of the main characters believes him.
 * In the later season episode "Ethon", both the Rand Protectorate and their political and military rival, Calledonia, would rather nuke each other into the stone age than unite to oppose the impending Ori invasion. Even when a peaceful solution to their rivalry is offered, they still launched nuclear missiles against each other...
 * The Wire runs on this trope.
 * From Torchwood: Children of Earth. Say you're the British government. Say you have an alien problem. You also happen to know of an organisation which fights hostile aliens. It is willing to work with you. What are you going to do? That's right,
 * On Lost, Jack Shepherd's statement that "Either we live together or we die alone" qualifies. Subverted in the Fourth Season Finale when Jack started to say it, only to have Rose interrupt to notify him that if he did so, she would punch him in the face.
 * Doctor Who
 * In Revenge Of The Cybermen, one set of Vogans risks them all in an attempt to escape their hiding. Conflict ensues.
 * In Warriors Of The Deep the spies for the other human bloc use the alien attack to cover up their own activities.
 * Happens a lot on Law and Order and its spin-offs. Typically, it comes when a case happens involves multiple jurisdictions for various reasons.
 * New Jersey officers are portrayed as competing with New York ones for the chance to get the 'collar' (arresting a suspect). In one episode, a DA even remarks that New Jersey has an 'inferiority complex' about the NYPD getting in their affairs.
 * Police departments in parts of New York north of New York City ('upstate') and east of it (Long Island) as being at the best laid-back local sheriffs who don't like city-slicker interference and at worst in on the crime.
 * Virtually all crime dramas portraying city-level police portray Federal authorities as authority wielding Men in Black who are all too willing to let a horrific crime go unpunished to further what they see as a bigger picture.
 * Dead Set uses this trope effectively:
 * The only reason that the virus reaches the inside of the Big Brother house is because the housemates refused to believe Kelly.
 * Grayson refuses to kill an infected
 * , against the wishes of the rest of the group. The result?

Tabletop Games

 * Warhammer 40000 takes this to insane levels (look at how many Literature examples it has!). 'There is no innocence, only shades of guilt.' Everyone is held in the darkest suspicion of heretical thought, Entire worlds are lost while organizations bicker over their jurisdiction. The only person above reproach is named the The Immortal God Emperor of Mankind and he might be dead.
 * The Imperium has at least half a dozen Thoughts For The Day dedicated to this, among them "Divided we stand, united we fall". Considering the extreme hierarchical nature of the Imperium, a few higher-ups going rogue could (and has) lead to massive problems - Some regiments probably only recognized their superiors turning to the side of Chaos a few weeks after being told to paint those cool stars over their old insignia.
 * The present Imperial is extremely decentralised, though, after the Thorian Reformation no one power group has control over the Imperium, and there are several extremely powerful watchdog organizations in place to control abuses of power. And burn heretics, of course.
 * Said organisations are also hanging separately. The Inquisition spends hours in philosophical debate with a bolter in one hand and a power sword in the other. Oh dear.
 * Exalted, oh so very much. Solars, Lunars, Sidereals and Dragon-Blooded are all trying to protect Creation in their own way; it's just that the Dragon-Blooded's way involves demonizing all the others to keep their orderly society going, the Sidereals' way involves manipulating said society from behind the scenes because they don't trust any of the others with power, and the Lunars' way involves tearing down said society because of its increasing corruption and instability. The end result is Creation's heroes spending a whole lot of effort fighting each other when they could be fighting the Abyssals, Deathlords, Fair Folk, and other forces who want to destroy the world.
 * Hunter: The Vigil has its own version, as a good number of the Compacts and Conspiracies are at direct odds with one another. Let's see, Task Force VALKYRIE wants to deal with the supernatural in secret, while Network Zero wants to blow open the Masquerade through new media. The Long Night are premillenialist Christians aimed at "redeeming" monsters who view the Malleus Malificarum, the Catholic Church's black bag group, as followers of "the Great Whore of Babylon." The Philadelphia sample setting takes it a few degrees further, with the general mood of "Not In My Backyard" and an emphasis on how the hunters are more devoted to territorial pissing than, you know, monster hunting.

Video Games

 * This is a prominent theme in Starcraft. Particularly the first Terran campaign, which is almost entirely about humans fighting each other, rather than fighting aliens. The Protoss Judicators are also more worried about the Dark Templars than they are about the Zerg. The dominant force at any moment is the faction that is able to act as a unified team without infighting. Not even the Zerg are immune.
 * This happens in the GDI campaign of the original Command & Conquer. Partially due to propaganda made by Kane, the United Nations temporarily cut military funding to the GDI. For a few missions, the commander is left on his own to fight without vital base structures.
 * A little distraction like, lets say... a fullscale alien invasion is not a reason for Nod and GDI to quit fighting each other. This caused some irritation by the aliens, calling humans "warlike to the extreme". However, neither the GDI nor the aliens knew that it was all according to Kane's plan.
 * In the fourth game, a civil war was fought between.
 * In Mass Effect, Ambassador Udina tries to stop you from  because it might damage humanity's reputation (granted, he didn't believe you were telling the truth, but still).
 * The World of Warcraft is being afflicted by this trope as we speak. Are the Horde and Alliance forces facing off against the Lich King? Sometimes. They are also, at least as often, invading each other's cities, declaring war, and, lest we place all the blame on poor Varian Wrynn, ambushing an Alliance force that was winning against the Scourge, wiping them out and then getting roflstomped by the Scourge themselves, thus handing the baddies two free battlefields' worth of corpses to play with rather than negative one. And their commander praises this behavior. Meanwhile, the Argent Crusade and the Knights of the Ebon Blade bang their heads against the wall in frustration look at each other, shrug, and get back to kicking ass.
 * In Suikoden Tierkreis, this plagues the Magedom of Janam. The Mage Forces are led by Danash VIII's first wife, Shairah; their Arcane Acadamy is headed by his second wife, Rizwan. Then there's the Blades of Night's Veil, commanded by Chrodechild, who Danash wants to take for his fourth wife—yes, there's a third, who complicates things even more without her own command... Needless to say, they have problems without The Order of the One True Way breathing down their necks.
 * Arcueid seems to have little issue with cooperating with the Church when necessary. They, on the other hand, feel differently as she's technically a vampire as well. Fortunately, she's essentially indestructible so they decided 'Fuck it' and agreed to work with her on occasion. That's mostly background material due to our only seeing sane Church members, but Ciel and Arcueid also have a funny tendency to start fighting to the death when differences arise. And they're friends.
 * Dragon Age takes this trope and runs with it. At the end of the first (non unique) chapter, The Wardens themselves are then persecuted from one side of Ferelden to another, even as the darkspawn steadily devour the countryside.
 * Worse, a civil war starts when . It also helps(?) that doesn't believe that a Blight is occurring and thinks the Wardens (who know that a Blight is happening) are enemy agents from a country that occupied Ferelden and ruined his childhood. Since  is a war hero that freed Ferelden from said country a lot of his supporters follow him even as he grows increasingly paranoid and commits greater atrocities to protect his nation.
 * Used to great length in Dragon Age II with multiple factions warring against one another. The templars and the mages fight constantly, even though they should be working together to help everyone in Kirkwall. Members of the Chantry oppress the qunari, who in turn try to overtake Kirkwall in disgust. This even occurs with members of player character Hawke's party. If Hawke picks a side in the final act and the party members on the opposing side don't have their friend or rivalry meter high enough, they'll leave the party. In some cases, they may even try to kill Hawke.
 * Pokémon Gold and Silver has your rival. He hates Team Rocket beacause . But on the other hand, he absolutely hates the player character, pushing them around, and even . He's actually the worst rival; Kanto's rival says things like "Smell ya later!", Hoenn's rival is a pretty good friend, and Sinnoh's rival is your best friend.
 * In Infinite Space, Yuri points out this is the reason why . To elaborate, . And in Act 2, the LMC nations almost made the same mistake...
 * Yet another Warhammer 40000 example is in the Dawn of War series, which contains five different campaigns (so far) in which everyone would much rather kill everyone else than work together to defeat the Orks, Necrons, Tyranids, and/or Chaos that are rampaging everywhere. This ranges from Winter Assault, in which the Imperial Guard and Eldar briefly ally before arbitrarily betraying each other, to Soulstorm, in which three different divisions of the same faction are pounding at each other.
 * It gets lampshaded repeatedly in the sequel, especially the Retribution expansion, as you can hardly go two plot-centered missions without someone calling out their same-side enemies on how there's such a bigger issue at stake. The Space Marines deal with the obfuscating Senator, they end up fighting themselves when Chaotic corruption begins to infiltrate their ranks, they have quite a few bitter issues with the Guard, the Eldar want to wipe out the entire planet rather than fight WITH the Imperium against the Tyranids, etc. Ironically enough, only the Inquisitor (the one usually most hell-bent on driving wedges between factions) seems willing to use cross-faction Alliances, even enlisting the Orks as mercenaries during their campaign.
 * Final Fantasy XIII. Five individuals are given Stock Super Powers and sent on The Quest of vague nature, just like in so many Player Party-based RPGs. The problem is that two of them hate the third one's guts, the fourth has a hidden agenda, and the Only Sane Man is appalled by the others so much, he decides to quit. And none of them has the same idea of how to treat their new Cursed with Awesome status and go about their quest.
 * Nine Hours, Nine Persons, Nine Doors. Suffice it to say, that isn't how the nonary game was supposed to end.
 * Nine Hours, Nine Persons, Nine Doors. Suffice it to say, that isn't how the nonary game was supposed to end.

Webcomics

 * The Light Warriors of Eight Bit Theater spend lots of time trying to kill each other. Word of God has said the monsters and obstacles that they face in the world are nothing compared to the monsters and obstacles within the party.
 * The Dreamland Chronicles: The dwarves don't believe that the elves did not attack with the Nightmare Realm.
 * And accuse the elves of treason.
 * Bob and George. Trying to warn Dr. Light doesn't work well.
 * In Impure Blood, having been attacked doesn't keep the Watchers from spending all their time quibbling—including about whether they should be Ungrateful Bastards toward Roan, and if so, Who Will Bell the Cat?.
 * Dara has had enough of it.
 * In American Barbarian Yoosamon's urging that he form alliances hits this.

Western Animation

 * The American military in Justice League Unlimited spends so much time making superweapons to defend against/destroy the Justice League, they completely ignore the fact that relying on Lex Luthor as opposed to the people who are busy saving the world every day might actually be a bad idea.
 * To be specific it was because of Project Cadmus's idea in recruiting villains to do their work for them.
 * In Avatar: The Last Airbender, Long Feng, the Evil Chancellor and default ruler of Ba Sing Se (the capital and last major outpost of the Earth Kingdom) refuses to aid and actively hinders Avatar Aang, The Chosen One, in the fight against the Fire Nation.


 * On a larger scale, this has played out in the war as a whole. The Fire Nation launched an overwhelming strike against the Air Nomads, managing to commit genocide without any other nation coming to their defense (at least successfully). The Water Tribes and Earth Kingdom then decided to see to their own defenses, with the Southern Water Tribe only coming to the Earth Kingdom's aid 97 years into the war.
 * The Southern Water Tribe had been enduring constant raids by the Fire Nation for sixty years before the beginning of the show, so they had their own problems to worry about. The Northern Tribe, though? No excuse.

Real Life

 * A classical parable concerning this is about the sons of king (I think) Attalus of Pergamon (although similar motifs seem to reoccur about a lot of different people) and his large number of sons. As they were squabbling over who would succeed him, he took a bundle of spears and asked his sons that whoever could break them could succeed him. No one could. The king then took each spear in turn and broke it easily, making a point about unity being strength.
 * Variations of this parable have since been recounted far, far too many times to count, in both history and fiction. When it's not representing the fascist movement, it's illustrating the key to defeating Cao Cao, or teaching three young brothers about The Power of Friendship. Has nonetheless avoided becoming a Dead Horse Trope.
 * Also shows up in King Lear and its most famous adaptation, Ran. Subverted in that the daughters of Lear/the sons of Lord Ichimonji don't learn the lesson and things get worse. Much worse.
 * Parodied in a Lineage 2 comic where an orc father tries to teach his quarreling sons this lesson... but is stronger than he thinks and easily breaks the united spears. He makes the best of it and converts it into a lesson in the importance of overwhelming strength.
 * The metaphor for this "strength through unity" approach is visually symbolized by a bundle of sticks often including an axe and is called a fasces. It is commonly found in art and heraldry all over the world. Its use has lessened somewhat after Mussolini adopted it as his symbol and named his ideology after it, but unlike another symbol we could mention, it is still fairly easy to find, particularly in the United States (where the old national fondness for Roman imagery and the institution of federalism make the fasces an opt symbol) and France (they're on the semi-official arms of the Fifth Republic).
 * A warning against this was attributed to Benjamin Franklin at the signing of the Declaration of Independence: "We must all hang together, or assuredly we will all hang separately."
 * Extremely prevalent trope in real like: every organization has some degree of political infighting and factionalism. Patton himself said that 'Competence in the battlefield is a myth. The side who screws up the least wins.'
 * Another example, although this time it applies to the bad guys: towards the end of World War II, prominent Nazis were tearing each other apart to succeed Hitler, despite the advancing Allied and Soviet armies. This continued until the literal last days of the war.
 * The Byzantine Empire indulged in this all too frequently. Internal political squabbling at the Battle of Manzikert whilst on the battlefield with the enemy was a major cause of the Byzantine defeat there. Their army was almost destroyed, and the Empire never fully recovered. A century or so later, after Constantinople was conquered by the Venetians and their allies during the Fourth Crusade, the three Byzantine kingdoms that formed from the remnants of the Empire spent more time fighting each other over the Imperial title than trying to take their city back. All the squabbling between Christian Balkan states pre-Turkish conquest partially fits this trope.
 * An absolutely PERFECT example is the Battle of Arausio circa 107 BC. Two Roman armies were raised to stop the advance of the Three Germanic Hordes (Teutones, Cimbri, Marcomannii), one led by a Patrician, and one by a Plebian. The Patrician, Quintus Servilius Caepio, absolutely HATED his counterpart, to such a degree that he refused to go along with his plans to merge the two armies as one and wait for the German attack. Caepio kept his army separated due north of the other army, and when the Germans came, they swarmed over his army and utterly crushed it, then waited a short time before swarming over the other army next. Nearly 100,000 Roman soldiers and camp followers were killed, nearly twice as many as the Battle of Cannae.
 * Even when the Imperial Japanese Army was rampaging out from Manchuria into the rest of China, the Chinese Nationalists and the Chinese Communist forces often spent more time fighting each other than defending against the invasion.

"Lord protect me from my friends, I can handle my enemies myself."