[identity profile] keithmm.livejournal.com 2015-10-09 07:11 pm (UTC)(link)
An analysis I've seen pegs the problem to two things: gerrymandering and the elimination of earmarks.

The Republicans have created House seats so safe that they don't have to worry about appealing to a wider spectrum of the voting public so the only challenges they have to worry about are coming from the right. And while earmarks were a source of needless spending, they were also a way Congresscritters could bring government benefits directly to their districts and fund projects that needed to be funded. But that meant the member in question would have to be open to negotiation and horse-trading in order to get their earmarks in, and if a member started going too far off the reservation, the leadership (and other members) could pull their support and the rep would have a problem bringing benefits home, which would hurt them come election time. *And* they couldn't be so rabidly anti-government as to want to shut the whole thing down, because it was government that was required in order for them to bring the presents home.

[identity profile] seth ellis (from livejournal.com) 2015-10-10 02:23 pm (UTC)(link)
*And* they couldn't be so rabidly anti-government as to want to shut the whole thing down, because it was government that was required in order for them to bring the presents home.

A political scientist I know puts it this way: What kinds of people are anti-government, and therefore run for government? Idiots and crooks. This has perennially plagued the more conservative outlying districts for the Republican Party. But now—thanks to gerrymandering and no earmarks, as you say—they're all outlying districts, and there's no percentage in a crook who isn't an also idiot getting into Republican electoral politics in the first place. The more usual sane-but-craven politicians have been fleeing the Republican Party for a while now; Boehner and McCarthy took people surprise only by how sudden and public their withdrawals were.