"From the director of Independence Day
" - Contains all the spoilers you need :
ncient non-Americans predict 'big space-rock' will destroy the earth in many moons time.
Many moons pass.
Americans laugh smugly at silly non-American ancient predictions.
'Big space-rock then hits earth'
America is devastated. So is the rest of non-America, but a few quick, panned shots of devastated non-American cities is enough to cover that unimportant stuff, which allows the focus to return to the true tragedy of 2012 - The destruction of America.
Never accepting facts, the plucky Planet America then saves humanity (because non-Americans are useless) by jumping on a spaceship and flying to a galaxy far,far away....."