Is congress irrecoverably corrupt?
I'd guess that the thoroughly bad apples comprise no more than 20 percent of the whole, but obviously that's just a wag.
Problem is, the bad apples seem to always succeed in slipping a dozen multi-million-dollar earmarks or loop-holes into virtually every piece of legislation they pass. They do this mainly by slipping their crappy, self-serving provisions into bills that are considered "must-pass"--as in, if congress doesn't pass it something unacceptably bad will happen.
Thus the majority of good folks are backed into a corner: If they want to keep funding our troops, or keep the gubmint running, or whatever, they have to vote yes on the entire, pork-laden, corrupt, earmark-riddled POS.
And of course, as long as voters in a handful of states keep electing corrupt people to congress, this problem won't be solvable.