Eli Lake has a sharp piece about Republicans who aren't comfortable with the Austerity Era focus on defense cuts. The kicker from Donald Rumsfeld is not as perceptive as it sounds:

Former defense secretary Donald Rumsfeld expects both sides to make concessions. “Our side agreed to defense cuts, their side agreed not to raise taxes. My sense is that neither one will stand,” Rumsfeld told Newsweek.

The thing here is that defense spending is no longer as sacrosanct as tax cuts among Republicans. Almost every Republican member of Congress has pledged to not raise taxes. There's no ideological cattle brand like that on defense cuts, and that's partly because the public has understood for quite some time that massive defense spending means there'll be some waste.

It's sort of odd that we accept this. In bygone days, being a "fiscal hawk" meant that you wanted things to be paid for. To be a hawk now is to want America to exert power when it needs to, and to make sure its military outmatches every other country's. To be a "fiscal conservative" means you want to cut spending and taxes. Nearly all Republicans supported tax cuts in 2001 and 2003, which also happened to be the years they supported new wars in Afghanistan and Iraq. Alan Simpson, safely out of politics, has pronounced this "bullshit." That's the hawks' problem: Demanding no defense cuts and ruling out ways to pay for them is just what Alan Simpson and a lot of voters think it is.