Man, what a fascinating idea for a thread! Too bad most of the movies I’d pick have already been mentioned.
Forrest Gump. Not my favorite movie, but, piecemeal as it is, it will give our returnees some idea of what’s happened.
Platoon. Probably the best movie to show about the Vietnam war, changing attitudes about the military, the depiction of violence in contemporary culture, increased pessimism about the U.S.'s role in the world, etc.
Wall Street. Two Oliver Stone movies, and I don’t even like the guy! (I might even consider showing him JFK, but only if we could give him a lot of material pointing out the BS nature of the movie’s theories, which we aren’t allowed to do by the OP’s rules.) This one’s a good intro to the modern American business ethic, and the “greed is good” ethic of Trump etc.
Either Malcolm X or Mississippi Burning. If anyone can think of a better movie about the Civil rights era I’d be all for it.
Hair. Hippies and silly musicals are two things they should know about.
American Pie. They’d better be prepared for frank, vulgar discussions about sex and rampant cursing.
Philadelphia Aids, and the more public presence of homosexuality, and the debates this openness engenders. Again, there may be a better movie than this
Do the Right Thing A look at contemporary race relations.
Three Kings America in the middle east, the media and war, Iraq.
The Net Yes this was a horrible, horrible movie. But it does give some warped idea for the centrality of computers in everyday life, and the diminishing of privacy. If anyone can think of a better movie for this, I’ll cheerfully exchange this. The Matrix is too fantastic for this purpose, IMO.