Comic books are mainly about superheroes fighting supervillains. There is a threat against innocent lives and it's up to the heroes to save the day. Heroes clash against their enemies, a battle is fought and the good guys win. It's almost a sort of brightly colored dance they do.
When superhero comics started gaining popularity, it was all fun and games. Did anyone really ever get hurt? Sometimes a hero would. Heroes even paid the ultimate price at times with their lives. But because they're superheroes, there usually is a way for them to come back from the dead.
Over time, the stakes got higher. The threats got bigger. Soon, it wasn't just superheroes or the occasional supervillain dying. More and more, innocent civilians started getting caught in the crossfire. Innocent humans were dying. The deaths started happening more often until the numbers were off the charts. Does the death of innocents add to the nature of superhero comics?
== TEASER ==
One example that comes to mind is in the first volume of The Ultimates. Bruce Banner turned into Hulk and went on a rampage. The Ultimates fought him to contain him but there was only so much they could do. During the battle, the Hulk's rage caused an immense amount of destruction. The death count was over three hundred. Three hundred lives gone just like that. It might not have been completely Banner's fault since the Hulk was uncontrollable but those deaths seemed insignificant. Banner stayed locked up in luxury while the PR department put a spin on the battle. Hulk was later released and used to fight off an alien invasion.
What about Ultimatum? Over a million New Yorkers were killed when a tidal wave hit the city. That's a lot of people. It was meant to be an insane amount to drive the point across to us. This was a new age. Villains didn't play nicely anymore. Throughout the rest of the series, there really wasn't a whole lot of attention given to the dead. In the end, the villain was punished and mutants were hated even more. The real focus was put on the dead heroes. They were the ones that mattered. The one million New Yorkers were just a simple statistic.
It could be that the Ultimate Universe has different rules. Things are more extreme. In the regular Marvel Universe, Hulk went on a rampage in Las Vegas. Twenty-six people, two kids and a dog were killed. This may not seem like a huge number compared to the other examples but these deaths, while not even seen, were the catalyst that started Planet Hulk and World War Hulk. It was questioned why Hulk was allowed to go on rampages and where would the death toll end? So he was shot out into space.
The death of innocents was also a big part of the current Wolverine arc, Wolverine's Revenge (in issues #'s 10-14). Wolverine has killed many people over the years. It turns out he's also killed many innocents at different points in his life. Of course the deaths at Stamford kicked off the Super-Human Registration Act and Civil War.
I remember when an innocent dying was a big deal. Remember when Captain George Stacy died saving a kid while Spider-Man and Doc Ock were fighting on a rooftop? Or even Gwen Stacy's death. Those deaths meant something. It was a shock and had a profound effect on Spider-Man. Hulk kills a bunch of innocent people (well, maybe they were up to some naughty things in Vegas...) but did he show remorse over the deaths?
When the death toll starts getting higher and higher, the impact of innocent deaths is insignificant. The other thing to consider is comic books are meant to be fun and entertaining. There is way too much death in the news. Do we really need to read about them in comics? Of course if civilians were never threatened or harmed, it would make things too easy for the heroes. There wouldn't be any seriousness to the superhero game. The possibility of innocents suffering is what drives most heroes. You can't have epic superhero/supervillain battles without casualties. It's just when the deaths go into the hundreds, thousands or higher, it becomes just a number without a lot of meaning.