The recent debate over the student loan rate hikes is a great example of the ways in which fundamental policy agreements can be obscured by other issues. In this case, Republicans and Democrats agree that student loan rates should not double this year. If these were the good old Bush Years that would be the end of it because, as Cheney allegedly said, "deficits don't matter", but nowadays everything but tax cuts for the rich have to be paid for. Which leads us to the confusing state in which the Democrats have blocked the Republican bill preventing the rate hikes, and Republicans have reciprocated. Democrats like to pay for things with tax increases on the wealthy, and Republicans like to pay for things with "dynamic scoring" and/or imposing further financial burdens on the poor and middle class.
Problematically, this issue has been spun by both sides as evidence that the other wants to impose rate hikes on students. The general public has a natural bias towards not giving a shit about accounting unless the political classes are really insistent that it matters, so politicians preferentially phrase disputes as policy disagreements. But a disturbing number of bills fail due to the same fundamental disagreement over how much money the government should spend, and where it should come from.
From my perspective, this is doing it ass-backwards. You figure out what you want to do, then you figure out what it should cost, then you figure out whether it is worth doing, then you figure out how to pay for it.
The Republican strategy is to pick how much they want to spend, and then eliminate social programs until they get far enough below that spending number to give some tax cuts to the rich. The Democratic strategy is to pick policies and pay-fors in an ad-hoc manner, which would be fine except that you lose sight of the greater context that way and you have to have two debates for each policy, one for policy and one for pay-for. A better strategy would be to work out a bunch of things you want to do each year, prioritize them, and pay for all the ones you can afford. But that would require a fair amount of consensus about a) priorities and b) how much can be afforded, and we have neither. Please can we get a parliamentary system?