spending on the military and government controlled GDP were huge in the falling of USSR, but i think what killed them is NASA
we "set" 12 people on the moon....this is what bankrupt the country. we used hollywood and NASA to create a huge lie that we made it there not once...BUT LOTS
the soviets had so many "failures" in their space program, never once getting a man past the ionosphere. the hoax wasnt just a lie and propoganda for americans but it ruined the soviets. supposedly we had better rockets, we supposedly made it to the moon, so in theory we could nuke the hell out of them. they gave up on the space race and tried to spend more and more on the arms race.
to this day we havent gone back to the moon even though the original iphone is a million times more badass than the computers they had in 1969, our technology is waaaaay better but yet we cant, and the excuses are lame and flail. we cant "go" back cause we never made it, one day the world will see it was the biggest lie in the history of the world, but it ended the USSR.