Huh. Imagine that.
In Fantastic Four: Life Story #2, the team's origin is retold through the lens of the era in which their comics debuted: the '60s and '70s. These are tumultuous times for everyone, superheroes included, and Americans slowly lose faith in their leaders and authority figures. As Susan Storm ponders the state of the world, heroes like Namor and Captain America take matters into their own hands. "Because when you can't trust those in charge to do the right thing...who else is there?"
The 1970s, in the aftermath of Watergate and approaching the eighth year of operations in Vietnam, was a difficult decade for a patriotic hero like Captain America. No longer could he be seen as a man who represented the United States government - and writers knew it. Captain America was eventually retooled into a man who put American's stated ideals before America itself (or its elected officials).
It's pretty interesting how the time period changes the characters so drastically. Imagine what superheroes debuting today would be like. At this point, if anyone's interested, I'd like to recommend the web-serial Worm. It's a much more realistic take into superheroes (without being all edgy about it). It truly takes into account how superheroes would actually change society (and has the most interesting power dynamics I've ever seen).