We have two interesting theories today about what’s happening in the House. One is from Neil Irwin, who posits that it’s all about a sunk costs fallacy — Republicans are mistakenly continuing to ask for things they can’t get because that’s the only way to justify what they’ve already given up by following their current strategy. The other theory, well-articulated by Greg Sargent, Jonathan Chait and Danny Vinik, is that Republicans are still fighting for the principle of extortion.

I strongly agree with the latter theory — way back in May, I argued that radical Republicans were fighting over the principle of extortion for the sake of extortion:

[I]t’s not really about Republicans demanding debt reduction and using the best leverage they have available to get it. Nor is it about Republicans demanding tax reform — their other possible demand — and using the best leverage they have to get it.
No, it’s the other way around. The House crazy caucus is demanding not debt reduction, not spending cuts, not budget balancing, but blackmail itself. That’s really the demand: The speaker and House Republican leaders absolutely must use the debt limit as extortion. What should they use it to get? Apparently, that’s pretty much up for grabs, as long as it seems really, really, big — which probably comes down to meaning that the Democrats really, really don’t like it.

It shows up all the time. For example, today Speaker John Boehner has pulled a delay of the medical-device tax from his latest attempt to put together a package, because the radicals weren’t happy with it. Yes, they have a plausible reason. But my guess is that Democrats have indicated they really wouldn’t mind eliminating that tax, and so it’s no longer a ransom worth asking; asking for something the Democrats only mildly oppose (or don’t oppose at all) misses the whole point of why they’re doing what they’re doing. “Extortion for the sake of extortion” certainly seems to fit with the wild GOP swings from Obamacare, to spending, to contraception, to who knows next as the next reason for the shutdown and debt limit threat.

The reason all of this matters, still, is because if it’s just a sunk costs error then the costs for Democrats in bailing them out are limited to whatever it is they give up.

However, if it’s extortion, then any perceived success establishes an incentive for future use.

The key, by the way, is perceived success. So it matters a lot whether Republicans believe that they actually are getting something whenever the final deal happens — much more than whether, in some objective sense, they actually did get anything.

It’s hard to read exactly who is thinking what while these things are going on. But if it really is extortion for the sake of extortion, at least for the radicals, then there’s a very strong incentive to Democrats to hang very tough.