The system of government isn't the problem. The way the system was set up it allowed for sweeping change in Washington. The two parties changed the system by pretty much eliminated any chance of a third party by excluding them from debates and making people believe that voting for a 3rd party is a wasted vote when reality is using your vote to keep someone out of office is the real wasted vote. The two parties have become so entrenched that they know they aren't going anywhere which has allowed special interests and back door politics to rule. Politicians, even the president in some cases have become pawns being controlled by corporate money and the behind the scenes party leaders.
Meanwhile, they have distracted us from the real issues while dangling ethic and moral issues like abortion, prayer in school, gay marriage as well as war and security while the real stuff happens quietly in the background.
In the end, it is our own fault for putting up with it and being so damn stupid.