Fallows has a must-read on the profound problems of the US constitutional system when the opposition party simply votes no on everything as a bloc. It's hard to come up with a better sense of the dynamic than this actual conversation that took place over the stimulus package:

"GOP member: 'I'd like this in the bill.'

"Dem member response: 'If we put it in, will you vote for the bill?'

"GOP member:  'You know I can't vote for the bill.'

"Dem member:  'Then why should we put it in the bill?'

Read the whole thing.