Europe DID need America after World War II - their economic help and military protection (not least by way of their new nuclear weaponry) is a major reason why the U.S.S.R. never managed to spread far beyond the Eastern Bloc. Even today, Europe's economy is absolutely dependent on the American economy - as our recent financial collapse shows. It's a balance of power that's shifting towards Asia, though, slowly, but the massive cultural ties between west-European nations and the US will play a strong part in keeping us tied to America for at least a generation or two yet.
On the subject of communism... there has never actually BEEN a communist nation, so it's kind of hard to say if it would be any better than our regular old capitalism. The Soviet Union and China both CLAIMED to be communist, but given that a communist nation has no government and functions on a complete and democratic equal share of the means of production, they're not really. They were socialist for a while, but Russia's long since fallen into the free market economy, and so has China, though they'd deny it vehemently in public. This is the major problem with communism: it doesn't actually seem to... work.
Also, capitalism is not pushed just by the 1% - in the western world it's pushed just as much by the middle classes, and in developing countries like China, even the lower classes are buying into it as their standard of living rises. It's true that with their immense resources, the wealthiest few wield tremendous influence over our politics, but the only way wealthy people stay wealthy is if they have lots of poorer people to support them. Should there be a fundamental shift in the way the lower- and middle classes think about money and economy (like, say, towards a collective communal model), the upper classes would have to either follow that shift or collapse.
It's a pretty damn complex issue, though, and I heavily suspect there is no real answer.