i think obama has continued the major shift to the right that represents whats happening in america in the last 20 years, clinton was center right throughout his presidency, and the major policy issue of our generation (healthcare reform) was co-opted to become a bastardized progessive reform. i have said ever since i was able to vote in 2004, there hasnt been a candidate running for major office thats liberal enough for me to vote for with good conscience. the only names that come to mind are kucinich and bernie sanders.
our country runs on the principle that he who has the most dollars gets the most power. right now its the major corporations who control political discourse (look at who runs the major media corporations). we have the democrats who would be a right wing party in any other country, and the republicans who have drifted so far to the right that they are basically advocating a theocracy on par with the hyper conservative leaders of some of the more repressive middle eastern states.
i wont be so dramatic as to say that our country is doomed, but the struggle needs to move from separation of church and state to the seperation of capital (money, to be vulgar) and state.
edit
quite simply, i blame 9/11 for forcing us further to the authoritarian side of the spectrum
also, i used principal when i should have used principle... fuck the english language, i suck at it