One of the reasons I think a government shutdown is inevitable is that Republican voters, much more than Democrats, want their leaders to stick to principles and avoid compromise. The latest Pew poll shows 63% of Republicans favor leaders who "stick to their positions" rather than "make compromises with people they disagree with." Just 48% of Democrats say the same. Even aside from the underlying desire by the GOP for large spending cuts, Republican voters are less attracted to compromise as a matter of general principle.
Why is that? Ezra Klein thinks it reflects the fact that we have a Democratic president known for preaching compromise. That may be part of it. I suspect it reflects the underlying differences between conservatism and liberalism. Liberalism is an ideology that values considering every question through the side of the other fellow and not just through your own perspective. In foreign policy, American power has to be constrained within universal principles. In social policy, the views of every group must be considered equally. In economic policy, the poor should count as much as the rich. Conservatism is more often the expression of self-prerogative -- we're the greatest country on Earth and we won't apologize, dammit. We're not afraid to stand up for traditional values, even if some Americans don't share them. And we'll defend rich people keeping what they earn.
The stereotype of liberalism, which is sometimes true, often runs toward bending over so far backward that you can't make obvious moral judgments: Who are we to judge this or that dictator? Criminals are just the result of bad environment. In any case, the joke about liberals -- a liberal is somebody who won't even take his own side in an argument -- is not a joke you'd hear about conservatives. Now, I think the qualities of confident assertion of principle and willingness to bend both have their place. One of my meta-beliefs about, well, everything is that one needs to be able to understand both black-and-white situations and shades-of-gray situations. In any case, I think conservatives tend to err toward the black-and-white worldview, and liberals toward the shades-of-gray worldview.