From Tim Ryan, Lisbon, Maine:
I read online in the Answer Man section of your website asking for movies where a better America emerged, Post-Apocalypse. I can think of a few movies where this happened. You may not think all of them are good movies but they are movies where a better America has emerged nonetheless. These are in no particular order.
1) "Independence Day" - OK, America winning the battle against the aliens notwithstanding, all of mankind immediately dropped hostilities toward each other in World Peace by being united against a common alien enemy. It also show that, despite Washington, DC being left in shambles, the ideals that the country was founded on survived as we see the kids of Randy Quaid's deceased character accepting a medal on his behalf on the steps of the ruined Capital Building. Democracy endures!
2) "Battle For The Planet Of The Apes" - OK, love it or hate it, this movie did have a very happy ending. After waging battle against an army of radioactive contaminated humans, the Apes and the human slaves of the newly formed Ape City band together to fight the intruder. Realizing that they are no better than their previous captives, the Apes give the humans their freedom. The scene then cuts a few hundred years into the future where the Ape Lawgiver (John Houston) is seen telling the story of this battle to a group of Ape & Human children. The message is clear that in order to thrive one must look beyond race or in this case species to find & keep their "Humanity."
3) Stephen King's "The Stand" - This may have been a TV movie but dammit it was still a good movie either way. After a plague has wiped out most of humans in America, a few survive. There is one final battle between good and evil where Good of course wins. The remaining humans have established a community of elected government. Everyone is seen doing their part to rebuild their community and to ensure that past mistakes are not repeated.
4) "Star Trek: First Contact" - The crew of the Enterprise D (Next Generation) are accidentally sent back in time to when humans are recovering from WWIII and are developing Warp Drive. Despite the pockets of life living in the wasteland flattened by nuclear weapons, the existing government is seen as the early form of what will eventually become the United Federation of Planets after they achieve Warp Drive and hook up with the Vulcans.
5) "Red Dawn" - This movie was about WWIII and the invasion of America. So I think it counts as being Post Apocaplyptic. Without rehashing it all, the movie did show that the fighting spirit of Freedom & Democracy is what built this county and what saves it in the end. At the very end of the movie we see that the small handful of teens who banded together to fight the aggressor were looked upon as heroes by the next generation.
So those are movies that come to my mind right off. I will admit it is slim pickins, but all of the above were mainstream movies seen by a lot of people.
I do hope you hear from some other folks. Maybe you can post a list of them on your site sometime. That would be pretty cool?