During a hero vs villain attack a hero named nitro exploded killing 600 civilians in the process. Public opinion turns against superhero’s labelling them “baby killers.” Guided by Iron Man, Congress passes the Superhuman Registration Act (SHRA), 6 U.S.C. § 558, requiring the registration of all persons with superhuman abilities with the U.S. government, and the enlistment and training of all aspiring superheroes. The law applies to those with naturally occurring superhuman abilities, humans using exotic technology (e.g. Iron Man), or anyone who wants to challenge superhumans. Characters within the Marvel Universe superhero community split into two groups. One advocates registration as a responsible obligation, and the other opposes it, arguing the act violates civil liberties and the protection secret identities provide. While arguing with Iron Man about the law, African American hero Luke Cage compares the mandatory registration to slavery. A number of villains also choose a side. Captain America refuses to join a S.H.I.E.L.D. strike force hunting violators of the act, and is attacked by S.H.I.E.L.D.'s "Cape-Killers" before the act is passed. He subsequently becomes a fugitive, and forms an underground resistance movement calling itself the "Secret Avengers". This team includes Hercules, Falcon, Danny Rand (who is acting as Daredevil in Matt Murdock's place), Luke Cage, and the Young Avengers Civil War explores the conflict between freedom and security against a backdrop of real-life events and discussions, such as the U.S. government's increased surveillance of its citizens in response to the 9/11 attacks.[2][3] The plot revolves around the U.S. government passing a Superhero Registration Act to ostensibly have super-powered individuals act under official regulation, akin to law enforcement. Superheroes opposing the act, led by Captain America, find themselves in conflict with its supporters, led by Iron Man. Spider-Man is caught in the middle, while the X-Men remain neutral for mutantkind's survival. The superheroes supporting the law, including Mister Fantastic and Ms. Marvel, become increasingly authoritarian. This should split up many hero groups like the fantastic four and leave many hero’s questioning their alliances