In a good article, Jonathan Chait lays out seven reasons “Why Republicans Will Never, Ever Have a Real Health-Care Plan”:

1. It has been a truism of American politics for decades that American voters are symbolically conservative and operationally liberal: They favor small government in the abstract but they like most actual programs. As Grossmann and Hopkins point out, this allows both parties to see themselves as representing the majority.

2. Republicans overwhelmingly describe their preference in ideological terms, Democrats in practical terms.

3. It also holds true among activists, among whom the Republican base is far more committed to conservative principle than the Democratic base is to liberal principle.

4. Democratic voters are also more committed to specific government programs than to the general idea of government. Republicans believe in cutting government in general but don’t want to cut many actual programs.

5. Liberal opinion columnists are more likely than conservatives to write about specific policy proposals, while conservative opinion columnists are more likely to write about abstract ideology.

6. The Democratic platform is also more likely to invoke specific policies, while the Republican platform is more likely to discuss ideological principle.

7. Republican voters want their party to stick to principle rather than compromise. Democratic voters want the reverse.

Chait sort of brushes up, but never really describes what is the underlying factor (boldface added):

Republican senators aren’t interested in governing because that’s not really their job. I guarantee they’ll show up for the bills that enrich their major donors (Got Koch?). But the other stuff? That’s for gulling the rubes. The goal isn’t to enact meaningful legislation, but to offer feel-good utterances and kabuki theater that makes conservatives feel good, even if it doesn’t solve problems. If you don’t believe government can affect most concrete, tangible problems, you’re not likely to show up at all.

Republican senators really do understand what their jobs are. It’s just very different than what most Americans think it should be.

Because this is what motivates much of the rank-and-file (boldface mine):

While people have described Palin as engaging in identity politics, that sells identity politics short. Palin along with the proto-movement surrounding her–Palinism–practices what could be call ‘politics of the blood.’ It’s derived from Giovanni Gentile’s description of fascism: “We think with our blood.” …In Palin’s case, it’s an emotional appeal to a romanticized, mythical past of “real America.” And that’s why I think the fixation people have on Palin’s complete policy incoherence and ignorance is missing the point.

Her policy ignorance isn’t a bug, it’s a feature. Palin is conceptually and intellectually poor because her politics are not about policies, but a romantic restoration of the ‘real’ America to its rightful place. The primary purpose of politics is not to govern, not to provide services, and not to solve mundane, although often important, problems. For the Palinist, politics first and foremost exists to enable the social restoration of ‘real’ Americans (think about the phrase “red blooded American”) and the emotional and social advantages that restoration would provide to its followers (obviously, if you’re not a ‘real’ American, you might view this as a bad thing…). Practicalities of governance, such as compromise and worrying about reality-based outcomes, actually get in the way. Why risk having your fantasy muddied by reality?

Republicans have rallied their slavering Uruk-hai by turning every political issue, no matter how mundane, into an existential crisis for white nationalists. This has been successful in the short run, but, at some point, it makes actual governance nearly impossible. This is the lens through which the modern Republican Party must be viewed: it is a regionalist, white nationalist organization with a political agenda. Unfortunately, that’s no way to run a Republic.