The budget deal brokered by Senator Patty Murray of Washington and Rep. Paul Ryan of Wisconsin is, in many ways, a clear win for Republicans.

The agreement establishes spending at $1.012 trillion in 2014 and $1.014 billion in 2015, up from the $967 billion as established by sequestration. It provides $63 billion in sequester relief, which is partially offset by a $23 billion mix of spending cuts and “fees.” It doesn’t extend emergency unemployment insurance, or provide any other relieffor the long-term unemployed.

Yes, this deal precludes any entitlement cuts for the next two years, which, as Dave Weigel notes, is something of a win for liberals. But on the whole, it’s hard to see how Republicans have lost with this agreement, which comes close to the budget levels set in Ryan’s original “Path to Prosperity.” As the Wisconsin congressman argued this morning, “We got the Democrats, who are against any of the sequester, to agree to 70 percent of the sequester.” Sequestration tore at our threadbare social safety net, and this deal leaves the damage intact. For liberals, it’s a huge disappointment.

But to the conservative Republicans who forced a shutdown and two debt limit stand-offs, it isn’t good enough. Within minutes of its announcement, Florida Senator Marco Rubio—who is still mending fences after alienating right-wing opponents of immigration—denounced the agreement. The conservative purists at the Heritage Foundation, FreedomWorks, and Club for Growth are also unhappy with the agreement. “This is a significant achievement for the president, who believes that government spending is a panacea to America’s economic woes,” writes Heritage Action CEO Michael Needham in an op-ed for USA Today. Likewise, in a letter to supporters, Americans For Prosperity railed against the deal, “Right now Congress is making backroom deals to increase spending and the deficit to over a trillion dollars a year, which we can’t afford. They promised to cut spending, but instead are trying to spend even more!”

It’s this right-wing outrage that explains opposition from Senate Minority Leader Mitch McConnell and Minority Whip John Cornyn. “I remain convinced the Budget Control Act has done what it was supposed to do,” said McConnell to reporters. “It has been a success, and I hope we don’t revisit it.” Likewise, Cornyn said that he was “disappointed that apparently some people are willing to give up the spending caps for just more spending and no entitlement reform.” The problem for both is that they face primary challenges, and while they’re likely to keep their seats, it’s also true that established Republicans have been knocked out by more populist opponents.

Which gets to the core dysfunction of the modern GOP. In a healthy political system, the parties make a trade: Democrats will support Republican preferences if, in return, they win support for their own. This was the model for the Affordable Care Act: Democrats were “trading” a market-based exchanges that preserved much of the status quo for near-universal coverage. The problem comes when one side—in our case, the Republican Party—rejects compromise as a matter of principle.

For the right-wing base and its institutional supporters, concessions are verboten. It doesn’t matter that this agreement establishes a conservative status quo for discretionary spending, and makes further spending unlikely. For right-wing Republicans, anything less than orthodoxy is a defeat, and defeat is preferable to working with Barack Obama and his allies.