(By Brendan Hoffman/Bloomberg)

But it does raise the question of why the Republican Party, which had just won a big election by running against the Democrats’ unpopular health-care plan, charged forward on a health-care plan they knew would be unpopular and, crucially, knew couldn’t pass. Because that’s really what’s weird here: It’s one thing to support unpopular legislation that you think is important and that you can pass but may hurt you at the polls. The tradeoff — good policy, bad politics — is clear. But what’s behind the Ryan tradeoff, which was bad politics in return for no policy? A few hypotheses:

1) They thought the pollsters were wrong and the plan either wasn’t unpopular or wouldn’t be unpopular once they explained it.

2) They were less worried — at least at that moment — about what would be unpopular with the electorate and more worried about what would be unpopular with the base.

3) They really believed in the Ryan budget, and were willing to lose seats, and perhaps even the majority, over it.

4) They believed that the details would matters less than their conviction. That is to say, being seen as “making hard choices” would be more popular than the choices themselves would be unpopular.

5) It fit the individual needs of key actors at a particular moment in time: Boehner needed to support something bold and conservative, Cantor needed to be pushing something more conservative than Boehner seemed comfortable with, Tea Party politicians needed to show they weren’t getting sucked into Washington dealmaking, Ryan needed to make good on his promises to take on entitlements, etc.

Presumably, all of these factors had a role in the GOP’s decisionmaking, But ultimately, this seems like a failure at the top. Boehner didn’t have the trust of his caucus and he wasn’t secure in his position and so he couldn’t play the strategic role that normally falls to the leader. The comparison with Nancy Pelosi is instructive here, as she was very trusted by the liberal wing of the party, and so she was able to persuade them to drop ideas, like the public option, that she eventually concluded were undermining larger objectives.