For many, being a superhero is something they fell into by accident. For others, it's a calling. But for these guys, it's just a day job.
A Military Superhero is a character who is or was a member of the armed services, and his experience as a soldier has colored his attitude towards the cause for the greater good. The discipline and training of the armed forces lends itself well to producing a pretty badass individual, and their codes of ethics and duty compliment the higher calling of heroism in such a way that they will, undoubtedly, stand out amongst their peers as someone who is reliable and sincerely committed to the cause.
This doesn't mean the hero is perfect by any means: military heroes tend to be pretty old-fashioned and stubborn in their beliefs, and also have a tendency to shun heroes who take authority lightly. They also often harbor disdain for authority themselves when serving under what they think is a weak leader, leading them to either try to take charge or just do things on their own. However, they are also the definition of esprit-de-corps within their organization's ranks, and will be the first to volunteer for any mission if it means keeping their teammates away from harm, as well as be the one guy you can always count on to never leave a man behind.
Very often, the character's background can actually come back to bite him. Their military superiors might come to them with a mission that goes against their current ideals as a hero. Perhaps a teammate does something that goes against the ethics he learned in the military. The bottom line is that this character can face many moral quandaries revolving around the conflict between his military background and his current status as a hero, which will always be played for drama as a way to deepen the story or make it more interesting.
Military heroes often exhibit stereotypes of the branch of service they serve/served with: an Air Force hero can be expected to be an Ace Pilot and love to fly, a Marine hero will be tough and have a little bit of the Blood Knight in him (or, sometimes, even a Knight Templar), an Army hero will be very patriotic, etc. It's pretty much expected of a military hero to also be a Captain Patriotic, but this is not always the case. If they have a rank as part of their name, they will possess that rank.
There are a few specific characteristics a hero must meet to qualify for this trope:
- The hero's military background is an essential part of the character. He can't just merely be or have been a soldier. If you could substitute the character's background for, say, law enforcement or being a fireman, it's not this trope.
- The character must be a bonafide superhero. The Punisher, for example, doesn't count: he's more of an anti-hero than a hero.
- The work the character is featured in must not revolve around the military. Military fiction, no matter how fantastic, has soldiers as protagonists by default, so their military background is obviously not something that makes the character stand out. As such, the hero's deeds will not revolve around a military mission. He performs heroism for its own sake, not because of following orders.
- Captain America is one of the best examples of this trope. Loyal to his teammates, a born leader, a paragon of virtue and a bonafide ass-kicker. He was an actual captain during his time of service with the airborne rangers during World War II.
- Same goes for Bucky, Cap's onetime sidekick, since the revelation that his background was a cover story to hide his status as a covert assassin, and his later acceptance of the Captain America mantle.
- The Falcon is a U.S. Air Force officer in the Heroes Reborn continuity, and a retired member of the U.S. Army in the Ultimate continuity. His Heroes Reborn background was used for Captain America: The Winter Soldier.
- Captain Nathaniel Adam of the United States Air Force, better known as Captain Atom. Interestingly, Captain Atom did not start this way: he was a full-time soldier who received his powers as the result of an experiment, and was ordered by the military into infiltrating the superhero community to spy on them a keep them in check. However, as can be expected, Captain Atom eventually did grow to appreciate his role as a superhero, but not without serious conflict between both aspects of him. This is explored heavily in Justice League Unlimited.
- John Stewart, aka Green Lantern, is a former member of the United States Marine Corps. Originally, John's backstory had him as merely an architect before becoming a Green Lantern. The DCAU re-imagined him as a Marine veteran, and this version proved popular enough that his DCU incarnation was retconned to have been a Marine as well (while leaving his existing backstory intact; he became an architect after returning to civilian life). In his modern incarnation, his training in the Corps has been a defining part of his character and has served him in his job as a superhero. His experience as a sniper helped him take down Sinestro Corps member Bedovian by sniping him three sectors away, and in the Justice League animated series, he battled alongside US Army soldiers (among them, Sgt. Rock himself) in WWII when he didn't have access to his ring's powers.
- While Hal Jordan has always been a former Air Force pilot, his The New Frontier incarnation is the one that most fits this trope. His experiences as a pilot during the Korean War heavily influenced his attitude towards his later job as a test pilot and his role as the newest Green Lantern of Earth's sector. Hal's character is a typical hotheaded ace flyboy, similar to Chuck Yeager.
- David Reid, a.k.a. Lance, of the Justice Society of America. He's a member of the Marines when he's recruited and served as a kind of liasion between the two groups. Then he gets killed and comes back as Magog (yep, the same character from Kingdom Come).
- Colonel Nick Fury. Former sergeant in charge of the Howling Commandos during World War II and concurrent leader of SHIELD.
- His son Marcus Johnson (AKA, Nick Fury Jr.) is a Ranger in the US Army.
- Captain Metropolis from Watchmen is a former Marine lieutenant, while the Comedian is an inversion; he joined the US Army after leaving the titular superhero team, on bad terms.
- Kate Kane was discharged from West Point under Don't Ask, Don't Tell. She sees her vigilante activity as Batwoman as a form of military service that gives her life meaning.
- Wolverine has served countless times in the military, and has picked up a great many habits and skills with the years. Interestingly enough, he's always shown to be VERY serious and professional in that role, contrary to his usual authority-sticking personality.
- The ever-loving blue-eyed Thing had one of the most prestigious military careers in comic book history, having served as a pilot for both the Air Force and the Marine Corps. His exemplary service ultimately earned him the right to serve as an astronaut, which eventually led to that fateful cosmic radiation shower.
- Captain Marvel (Carol Danvers, formerly Ms. Marvel) was a Colonel in the United States Air Force and served with the Thing back when he was human.
- James Rhodes, aka War Machine, was a lieutenant in the USAF, and saw action in Southeast Asia. The Marvel Cinematic Universe retconned him into a Lieutenant Colonel serving in Southwest Asia.
- DC's Commander Steel was Hank Haywood, a US Marine who, after being injured during WWII, volunteered for special bionic upgrades that turned him into a Captain America Expy.
- Hellboy originally was a member of the B.P.R.D., a private agency that functioned much like a government military agency..
- The World Army in Earth 2 has a few: The Atom, Wesley Dodds and his Sandmen, Red Arrow, and Captain Steel. Red Tornado is "in progress," and Hawkgirl has gone AWOL.
- Venom's fourth host, Flash Thompson was an US Army volunteer soldier who lost his legs in combat and volunteered to become the symbiote's host when the military asks him to. In this case, it's kinda literal: Flash wears the symbiote like a soldier/mercenary uniform, instead of the famous "overly muscular black Spider-Man with razor teeth and monster tongue" version (though he occasionally takes that form on from time to time, when his control over the symbiote slips).
- The DC Comics version of Archie Comics' The Shield was a U.S. Army soldier turned into a superhero through a Powered Armor grafted onto his body after terrorists nearly killed him in an ambush. He served as the Army's top superhuman operative.
- More of a military supervillain, but Deadshot's New 52 incarnation is a former Marine. And as rotten as he is, he DOES save the world as a member of the Suicide Squad.
- Similarly Adrian Toomes, The Vulture of Spider-Man fame, was a World War 2 fighter pilot before he founded his company, which is where he picked up some of his more acrobatic flying tricks.
- Trinity (2008): One of the various retcons that occur because of the reality shift that results from Superman, Wonder Woman and Batman (the titular "trinity") being removed from the universe by the villains of the story is that Supergirl's escape pod was found upon crashing by Navy S.E.A.Ls and she grew up as a Military Brat, eventually becoming an Army colonel and superpowered agent answering directly to the President of the United States code-named "Interceptor".
- A part of Professor X's backstory is being a soldier (originally in The Korean War, though thanks to Comic-Book Time, it's now an unnamed conflict), where he got a Dear John letter from Moira Kinross before she married Joseph MacTaggert (which ended badly for everyone involved), saw his stepbrother become the Juggernaut in a temple they found, and met Kitty Pryde's father. That said, the only incarnation outside of the original comics that touched upon in the idea that Xavier was in the armed forces was the 1990s X-Men animated series.
- Skyrocket (Celia Forrestal), who eventually joined the Power Company, was a Navy Lieutenant who left the force after being denied transfer to a combat squadron by a superior who disliked the idea of women in combat and realized that with the armored defense harness her parents had been working on at the time of their murders she could work as a superhero instead.
- Rex The Wonder Dog started out as a bomb sniffing dog in WWII that was given an experimental serum meant to increase his intelligence and agility as a pup. His handler took him home with him after the war ended and Rex eventually gained immortality and fully human level intelligence, or above, after drinking from the fountain of youth.
- In The Institute Saga, the USA is noted to have formed an entire company of powered individuals, including two Serum-enhanced supersoldiers.
- The Marvel Cinematic Universe has many of the heroes listed in the Comics section above sharing the same military background, sometimes updated for the setting, updated to be contemporary with the films' release.
- Wearing the Cape:
- Blackstone, a superhero/stage-magician, is a former US Marine (he mustered out and began his stage-magic career some time after a battlefield injury rendered him incapable of field operations). He appears to have worked in military intelligence, and is the security/intelligence specialist of the Sentinels.
- After the events of the first book, a former military operative who trained supersoldiers is brought in under the code-name Watchman as the newest big hitter.
- There are also a number of superpowered soldiers appearing in various books; one source is special military programs where volunteers are put in high stress situations, which may trigger "breakthroughs" (the advent of powers). The military also actively recruits civilians showing useful powers as well as using supercriminals for high-risk missions in exchange for reduced sentences.
- In Shadow Ops, the central protagonist Oscar Britton was formerly an officer in the Army National Guard before he turned up Latent with his portal magic and was forcibly recruited into the US military's Supernatural Operations Corps. Britton's military training gives him an edge over the other members of his "coven" (supernatural squad), and after witnessing the excesses and violence and hypocrisy of the SOC, he falls back to his military upbringing and sense of honor and duty and finally rebels.
- Super Powereds has Captain Starlight, the first Hero, who had fought in World War II before approaching the US Government about his powers. Averted with most other Heroes, since obtaining a Hero license in the US requires going to one of five colleges with an HCP department, none of which are military colleges.
- Taylor Earhardt in Power Rangers Wild Force was an Air Force pilot before encountering an Animal Mecha and crashing on a Floating Continent. She's one of the toughest Rangers on the team, and easily the most no-nonsense (at least until Merrick shows up), "drafting" Cole in the season premier by gut-punching him. Oddly, she basically goes AWOL as a result - the guys at her old base have no idea where she is, and she even hides her identity when a Ranger mission takes her there. She resumes duty at the end of the series, dismissing the idea of her landing on an island in the sky as people reading too many children's stories. The exact same backstory also applies to her male Japanese counterpart, Gaku Washio, who was similarly a JASDF pilot.
- Also, Kai and Mike of Lost Galaxy were members of the soldiers protecting the Terra Venture colony before getting their shiny suits, and appear to still keep that role during it all (with Commander Stanton allowing it unofficially while never quite coming out and saying he knows.)
- In the Supernatural episode "All Hell Breaks Loose, Part One" (S02, Ep21), one of the Special Children with Super Strength is Private Jake Talley of the US Army, who was fighting in Afghanistan.
- Bunker in Sentinels of the Multiverse is a serviceman working with the latest in a long line of armored suits built by the US military. According to his backstory, he's the first one to actually work as a superhero, all previous uses of the armor being in military combat actions.