USA....the most powerful and successful democracy in the world.

What are the parameters to determine a democracy as successful? You should state those upfront in your post.

Given the dismal and low voter turnout during the past few presidential elections in the US, I would be careful before labeling it as a "successful democracy." Here's the percentage voter turnout during the past five presidential elections:
1988 - 50
1992 - 55
1996 - 49
2000 - 51
2004 - 57 (during an unpopular war, only a 6% increase from the previous election)

http://en.wikipedia.org/wiki/United_States_presidential_election#Voter_t...

As for informed voters, where people are more swayed by "Swift-Boat Veterans for Truth" and the hoo-haa of gay marriage rather than real issues that impact them (taxes, health, education), I would not consider the 50% who turn up to vote as very "informed."

I don't know about you, but given the role money plays, to me it looks more and more like an oligarchy than a democracy, where having huge amounts of money is a pre-requisite to running for an office/contesting an election. As I understand it, that's not the basis of a democracy.

So as I see it, your premise/basis of comparison already has some faults. And I haven't even said anything about voter disenfranchisement (among Africans-Americans) and voter fraud. If you really want to do a comparison of democracies, maybe a European or a South American country would be better suited than the US.