Republicans in congress are currently on track to partially shut down the Department of Homeland Security unless the White House agrees to cancel its deportation-relief program. This sounds a bit ridiculous on its face, and for months now Democrats have been eager to make political hay out of Republican obstinacy. And, indeed, the GOP's shutdown politics poll terribly, prompting Jonathan Chait to label it "the worst idea they ever had."
If you want to understand why conservatives are so determined to forge ahead, though, you should look at another poll — this Washington Post poll from the 2013 government shutdown.
It was really bad news for Republicans. People thought the shutdown was terrible, and they thought it was all the GOP's fault. Ultimately it came down to perceptions of the character of the players involved, with voters saying that Barack Obama tries to do the right thing for America while Republicans just play for political advantage.
Then in the 2014 midterms, Republicans enjoyed a really crushing victory. The party brand was so un-damaged by the shutdown fiasco that they won governor's races in Massachusetts and Maryland and Illinois.
Shutdown fever genuinely is a bad dynamic for the GOP because it chews up time that could be spent pursuing achievable goals. But the combination of how terribly the 2013 shutdown polled with the utter lack of consequences for it in 2014 is vital to understanding the current dynamic. As conservatives see it, the only thing Republicans have to fear is fear itself.