No, 2 parties aren't enough. To say that American political thought can be summarized into one of two boxes is to insult the American electorate. I believe much of the disenfranchisement of the American electorate is the result. Not only do many Americans feel their politics don't fit in 1 of 2 boxes, but the current monolith makes it seem nothing will really change. The problem is then, that our current system does not encourage more than two parties, because the possibility of "throwing out your vote" by voting for a minority party is quite real (see: 1992, 2000 elections). So how can the system change to address this? I think that current technology (the dangers of voting machines notwithstanding) allows us to implement a instant runoff election system, where one can prioritize their choices rather than just pick one from the list. Thus, if I can vote for Nader, but then if he gets last place, I can designate my second choice as Gore, I can vote with my heart AND my head.