Sliding Scale of Unavoidable Versus Unforgivable

"Always forbidden, on occasion mandatory."

- Songs of Earth and Power, Greg Bear

How desperate must a situation be for a certain action to be acceptable? How heinous can a course of action get before we decide that the Moral Event Horizon has truly been crossed?

If it wasn't so long, the "Sliding Scale Of Unavoidable Versus Unforgivable" could also have been called the "Sliding Scale Of I Did What I Had to Do Versus Moral Event Horizon".

In a Sadistic Choice, it can be argued that both options would be wrong, so unless you find a way to Take a Third Option, you will do wrong no matter what you do. Then again, in the same situation, it could be argued that both options are right; that they are both the "lesser evil", although in different ways. Furthermore, it's not like everyone is capable of taking a third option, as that sort of thing requires one to be able to think outside of the box, so to speak, and the power to overcome the measures set in place to restrict them to two.

Closely related not only to Sliding Scale of Idealism Versus Cynicism, but also to Sliding Scale of Silliness Versus Seriousness and Moral Dissonance, mixed with a heavy dose of Your Mileage May Vary. A highly idealistic plot might very well feature brave heroes who slay countless humans or humanoids, the mass-murder or even genocide being Hand Waved by dismissing the victims as Exclusively Evil.

Since a Principles Zealot and a Totalitarian Utilitarian measure this scale quite differently, they are very likely to mutually accuse each other of Jumping Off the Slippery Slope. To some extent, this is even true for their reasonable counterparts, the Ethical Hedonist and The Deontologist.

Of course, the issue of sliding scales and slippery slopes does not only include the active action of actively doing something, it also includes the passive action of inaction - to choose to do nothing and just let things happen is also a choice. A choice that you can be held accountable for, just like any other choice.

Also, when the Sliding Scale Of Unavoidable Versus Unforgivable comes up in a story, it can be either intentionally or indirectly. It's intentional when the writers decide to make the situation ambiguous and debatable. It's indirect when the situation is intended to be unambiguous, but the reader/viewer goes "waaait a minute". However, one can never really be sure what version was the intended one, considering that Word of God is vulnerable to Getting Crap Past the Radar as well as blatant RetCons.

Anime

 * Code Geass is all over the place with this one. In fact, it seems it's the main question the show poses: how far can you escalate to achieve your goal, however noble it was, before you stop being you?
 * Sailor Moon pretends to raise this question a few times, especially with the Outer Senshi (particularly Uranus and Neptune), who are less sold on The Power of Friendship and more willing to resort to more extreme, destructive tactics than the Guardian Senshi. If the team decides to go the "nice" route, though, it turns out that whatever awful thing was supposed to happen doesn't happen Or a third option arises. Or, if they go the mean route, it backfires. Also, anyone who makes a Heroic Sacrifice gets better. Point is, Sailor Moon ultimately comes down on the Unforgivable side, with a convenient Deus Ex Machina there to make sure that the "nice" choice always turns out to be the best.
 * Most of the subtext in the Trigun manga and a lot of the overt text is about this. Anime a good deal as well. Wolfwood is the avatar of I Did What I Had to Do; one of his catchphrases is the 'not to choose is also a choice' line mentioned above. Vash is determined to be a Wide-Eyed Idealist hardliner in the face of a Crapsack World and save everyone. Knives, meanwhile, falls somewhere between taking Wolfwood's approach to horrifying extremes and just being a megalomaniac.
 * Interestingly, Knives is generally saner and more rational in the anime and engages in less actual evil because most of the plot got carved out, but his reasons for deciding to Kill All Humans are by comparison spurious.
 * Legato, meanwhile, who's the fourth major psyche vivisected, doesn't operate in a universe where right and wrong are particularly meaningful concepts, especially not as guidelines for his own behavior. Although anime!Legato does invoke the idea that he and everyone else (except Knives) are awful, egotistical beings who don't deserve life.
 * The anime ending is more ambiguous, which is odd when it's generally less willing to grapple with difficult issues head-on. Though this is less head-on than extremely obliquely.
 * The argument of whether or not Griffith's infamous Face Heel Turn was justifiable or just plain vile is probably the most hotly debated topic within the Berserk fandom, second only to the question of Griffith's true sexual orientation - which we will NOT be getting into.

Film

 * Watchmen debates this trope. Is ? Rorschach knows his answer, and the others, though horrified, all seem ready to make the pragmatic choice given the state of things. Doc Manhattan doesn't weigh in except to possibly dismiss the concept of the ends justifying the means (since there is no real "end"). "In the end" it's left for the audience to decide.
 * This is pretty much the point of the Vengeance Trilogy (Sympathy for Mr. Vengeance, Oldboy, and Sympathy for Lady Vengeance), where you're meant to feel sympathy for the antagonists and question the deservedness of the protagonists' revenge, while both cross seemingly many a Moral Event Horizon in order to pursue their goals, only for it to just about excuse everyone based on what they've been put through by each other...
 * ...well, apart from in, where the antagonist is never presented as anything but a Complete Monster, but the deservedness of the protagonist's revenge is still called into question by the end.
 * Austin Powers deconstructs this with heavy Mood Dissonance scenes of Alas, Poor Villain: When the heroes kill a Punch Clock Villain in a funny way, the scene is suddenly cut to the victim's grieving family and friends.

Literature

 * Halfway through Harry Potter, Harry (and the reader) learns of Unforgivable Curses - Imperius, Cruciatus, and The Killing Curse - which are (as the name says) Unforgivable, and carry a mandatory life sentence in Azkaban if used. Cut to book 7: Harry, Hermione and Ron use the Imperius curse as part of an infiltration mission, and even the Cruciatus curse once or twice. Hell, Professor McGonagall uses Imperio at one point!
 * This isn't even touching on the Killing Curse, the third of the Unforgivable Curses. Of course, the use of that one would be justified in any situation where shooting to kill is a necessity (though wizards, with the specific nature of their spells, would find it more feasible to aim for mere incapacitation than a man with a gun would,) but Lord Voldemort and his cronies using it as their signature spell wasn't really good for its PR. Or, you know, the fact that its entire existence is for killing, since it can't be used to threaten or incapacitate even as much as a gun can.
 * As Harry learned in fourth year Defense Against the Dark Arts and from Bellatrix in Order of the Phoenix, in order to successfully pull off an Unforgivable Curse, you have to really, truly, mean it. The implication is that The Killing Curse requires intense vitriol, true hatred for the target (or towards one's own actions, as may have been the case with ). The spell is explicitly MURDER, not self-defense.
 * In the films, Moody even uses all three curses against a test animal in front of a roomful of students, without any of them even pointing out that he just said they were unforgivable. Also, Moody must have really hated that little critter for the Killing Curse to work, which raises the question of why.
 * Remember that and it makes more sense.
 * It's Voldemort's own fault that the heroes were free to use Unforgivables in Harry Potter and the Deathly Hallows, as the Ministry under his command legalised them with the intention of using them against his enemies. Isn't karma wonderful?
 * Three Worlds Collide and its extremely Shoot the Dog "True Ending", which inspired plenty of debate in the comments.
 * In The Dresden Files, Harry makes this argument, pointing out that if  takes the high road in Dead Beat, thousands of people will die.
 * tries very hard to make you believe that the decisions you make are unavoidable. At one point  went nuts on a mook and might have been able to save an injured Muggle if he'd let that mook run. This was before he knew that.
 * Harry has a minor one of these, with shades of My God, What Have I Done?, when he realizes how many antagonists have ended up dead in his cases. Bonus points for that being from a mobster.
 * toys with this line a lot, including using forbidden mind magic.
 * Harry's mother was known for pointing out the gray areas in this scale that she felt weren't adequately covered by the Laws of Magic, or were covered too harshly.
 * eventually crosses this line wholesale in one of the later books . Though he believes it was unavoidable, in the next book he gets convinced that it was unforgivable, based on the decisions that.
 * Harry frequently points out to whichever Monster of the Week that's trying to recruit him that while they're touting the unavoidable end of the spectrum, he knows that they'll push him to the unforgivable end pretty quickly.
 * turns out to be a massive Batman Gambit to teach Harry that it's possible to avert this trope.

Live Action TV

 * Star Trek: Deep Space Nine: This is what made "In The Pale Moonlight" one of the darkest episodes in Star Trek history. The casualty list in the war against the Dominion gets so bad, that Sisko feels he has no choice but to go against his Federation principles to trick the Romulans with a fake offensive against them in order to get their support. And when the trick is found out by the Romulan sent to verify the information, In the end, Sisko decides that having the stain on his conscience is worth having fewer lives lost.
 * Star Trek: The Original Series: In "A City on the Edge of Forever", Kirk had to make a terrible choice -- Kirk rather uncharacteristically didn't Take a Third Option, such as, say, trusting her with the truth.
 * In his defence, not only is letting  the safest and quite possibly most Starfleet-regulation compliant way, it being the historical case, but attempting to Take a Third Option by telling her the truth would have been very, very risky.
 * Doctor Who: Seeing the number of times you can make the Doctor contemplate this scale is the pastime of the show's writers, especially since the reboot. The Doctor had to kill his entire race in order to protect the universe from destruction, and even though he knows it was the right thing to do, he still feels guilt-ridden. Time and time again, he is forced to make the Sadistic Choice of killing and committing genocide for the greater good. On the whole, the show tends to fall on the I Did What I Had to Do side, though actions such as killing all the innocent Racnoss babies (well, the little Racnoss babies were probably going to devour the whole planet and go on a tear across the galaxy if allowed to grow up) tend to get the occasional What the Hell, Hero? from other characters.
 * It was less the choice, which was understandable, than the mindset in which he made it and how he carried it off that freaked Donna out. Although the whole ancient-racial-enemies-therefore-I-destroy-you bit probably didn't help.
 * Torchwood pulls it now and then too, but especially in Children of Earth, where Jack Harkness sacrifices his own grandson in order to prevent a tenth of all the world's children from being sold into perpetual mindless slavery for an alien race that wants to use their body chemicals as recreational drugs. Throws the whole Wouldn't Hurt a Child thing up for inspection. And Word of God says he couldn't even have done that had his Morality Chain not bitten the dust in the previous episode.
 * Buffy the Vampire Slayer provides us with three in the fifth season finale. First, Ben is convinced that he has no choice, and can either fail to fight a god or earn that god's favor. Second, Giles, saying he had to do it because, unlike Buffy, he's not a hero. Then Buffy faces what she's been trying to prevent, whether to kill Dawn or let the world suffer hell. In the end, she opts to.

Tabletop Games

 * Sooner or later, a DM who's a massive dick is going to put the player who's playing a paladin into a situation where, no matter what solution they choose, there's some interpretation under which it is considered classically "evil" and will thus cause them to fall. Since they've put the player in the situation in the first place, chances are they won't allow any creative solutions which allow the paladin to stay a paladin, either. A good DM instead makes them deal with it in character, and encourages taking a third option if they can find one.

Video Games

 * The Driving Question of Heavy Rain: "How far would you go for someone you love?" In short, would you commit increasingly immoral acts if they offered a slight chance of saving your child?
 * In Famous has one choice at a certain point where is hanging from one side of a building and several scientists from another. The evil choice is to not save the scientists, but it really comes down to the lesser evil rather than a choice that's outright wrong, and you aren't allowed a third option. No matter what your choice is, however, the result is always the same.
 * Mass Effect 2 has a very unique case of the series in the Arrival DLC. In this mission, Shepard is . What makes this unique is that.
 * Warcraft 3 has several examples of this in campaign mode, one of the reasons it's considered a very engaging plot. Possibly the most famous example is the Culling of Stratholme: the heroes come on a city that's already infected by The Virus, and the party splits over the decision of whether to purge the city before the citizens can turn into zombies.

Web Original

 * SCP Foundation: Procedure 110-Montauk.

Western Animation

 * Titan A.E. gets a happy cheerful ending, with the wonderful happy-for-everyone GENOCIDE and recycling of the antagonist civilization. The dissonance felt by parts of the audience may or may not be intentional, but is there in either case.
 * It should be noted that the antagonist civilization was genocidal itself and blew up the Earth in the first place.
 * In the novelization, it's revealed that the Drej annihilated Earth simply because humanity was reaching a level of technology where they could potentially challenge the Drej's supremacy. Emphasis on reaching and potentially, which, of course, makes the destruction of the Drej more of a Karmic Death.
 * This troper always thought that it was because the Drej 'mothership' was not in fact the majority of the Drej race, but rather a small fanatical group that decided to ordain the fate of whomsoever they saw as a threat to the Drej. Additionally, since the Drej are implied to have technology that is vastly superior to the titular Titan, it is only logical that they don't have the totality of their race aboard a single ship, when they could have.
 * The season-2 opener of Avatar: The Last Airbender spends time talking about this. Aang has always been a Martial Pacifist, but now that his Superpowered Neutral Side is a known factor, people are encouraging him to go visit the Fire Nation capitol and go all Godzilla on it for the sake of ending the war, and he can't decide what to do. (It's interesting to debate what Toph and Zuko would have said on the subject, had they been present.)
 * Also notable that in the finale immediately previous to this season, Aang wiped out a large Fire fleet while in the Avatar State and fused with the Ocean. Casualty estimates are of course not provided in the work, and fan guesses tend to range from the dozens to the thousands. Aang tends to be given a moral pass on that one, since he was pretty obviously not in control of his own actions at the time (the Ocean spirit continued the rampage even after Aang seperated from it).
 * Brought up once again in the series finale, with the interesting twist that Aang's definition of Unforgivable—taking even a single human life—is in sharp contrast to everyone else's, who all agree that the Fire Lord needs to be killed.  Aang's desperate search for another option drives the plot for the first hour or so.

Real Life

 * Hiroshima and Nagasaki. One the one hand, it ended the war in VERY short order, likely saving lives on all sides. On the other hand, they were still deliberate nuclear strikes with heavy residential zones within the radius of guaranteed destruction.
 * Whether or not it was truly unavoidable is still hotly debated. Historical arguments on this point should go elsewhere. The key point here is that as far as Truman (who was not privy to internal Japanese politics) knew, the only choices were the nuke or an invasion of the Japanese homelands.