In the movie: Doctor Manhattan’s quantumpowers win the Vietnam War, assuring the heroic Richard Nixon a third term.
Actually: Bereft of a giant blue superhero, the U.S. lost; Nixon resigned the presidency, albeit for unrelated reasons.
X-MEN: FIRST CLASS
In the movie: Evil mutants instigate the Cuban Missile Crisis and nearly trick the U.S. and Soviet fleets into starting a nuclear holocaust.
Actually: The blockade of Soviet missile ships was Armageddon-y enough without X-Men meddling.
TRANSFORMERS: DARK OF THE MOON
In the movie: JFK decides we must land on the moon after a spaceship from robot planet Cybertron crashes there. In 1969, Apollo 11 explores the wreck.
Actually: The moon landing never happened. It was secretly staged in a TV studio by Stanley Kubrick.