The soviet union collapsed because of internal politics. The US survived because of bailouts. "Too big to fail?" And right now western Europe is about to double dip. Western Europe has some very socialist tendencies in the economic system. Not pure capitalism.
When I say pure capitalism, I mean no welfare. The market handles 100 percent of the economy. No safety net. For people or companies.
but the bailout came from capitalism and was self financed, so the point is the US never collapsed, so capitalism has proven to be better than communism
every country has internal politcs, and internal politics do not happen in a vacuum, the internal politics that destroyed the soviet unions happened because the soviet union was broke, and it could not bail itself out the way the US did, so fundamentally the soviet union broke up because it couldn't sustain itself
i dont see what western europe having a double dip and having socialist policies have to with anything
pure capitalism says nothing about welfare, capitalism can exist with or with out welfare, it is correct that the us is not purely capitalist but that is because the government does own some property and it does interfere with the economy, like the bailouts for instance, but welfare and capitalism are not mutually exclusive
the fundamental difference between capitalism and communism has to do with private property and government control of the economy, i think maybe you are confusing communism with socialism