For his 21-hour floor speech decrying Obamacare, Ted Cruz is catching heat from a lot of his fellow Republicans. In the Senate, they disdain his not-quite-filibuster as grandstanding. “This is not a situation where you dig your heels in and Obamacare gets defunded,” said Senator Ron Johnson. “[The tea party] just want anybody who offers them a path, whether it’s realistic or not.” Said Senator Tom Coburn of Oklahoma, “To be told we’re not listening by somebody who does not listen is disconcerting.” The Wall Street Journal editorial page, usually on board for any assault on Obamacare, blasted Cruz’s maneuver as baldly ineffective.

The sum of all these reactions is yet more widespread Republican exasperation with Cruz. But while the GOP usually has good reason to treat Cruz like a wacko bird, this time, the GOP broadly has plainly laid the groundwork for his gimmicky Obamacare opposition. The Ted Cruz who completed that 21-hour Senate floor marathon is a wacko bird of the party’s own making.

Many of the same conservatives who are now denouncing Cruz’s tactics have strong claims to paternity over the GOP’s destructive obsession with Obamacare. They may see the specific tactic of shutting down the federal government in order to undo the Affordable Care Act for what it is: a losing gambit. And they may recognize that Cruz’s grandiloquent speechifying isn’t going to change minds in the Senate, where lawmakers planned to stripped a provision to defund Obamacare from the House budget as soon as Cruz stopped pleading on behalf of the bill. But odds are they will continue to relentlessly endorse defunding Obamacare, just as they have before.

This, even though the party’s obsession with defeating the president’s signature achievement is laying waste to the GOP’s long-term prospects. As my colleague Noam Scheiber argued in June, the Republican fixation with the Affordable Care Act harms their standing with Latino voters at a historical moment when they need to expand their favorability, and fast. It detracts from their ability to build an economic platform that aims for something besides massive spending and welfare cuts. And despite the GOP’s intentions to make defunding their banner 2014 issue, despite dozens of votes to defund the law and their broad failure to leverage the law in the last election cycle, Obamacare is really, seriously unlikely to go away.

So for someone like Senator Lamar Alexander to imply that Cruz’s grandstanding feeds impressions of the GOP as a do-nothing party is pretty rich. The Tennessee lawmaker has cast 23 purely symbolic votes against Obamacare that now comprise a major plank of his reelection campaign. For the Wall Street Journal editorial board to scoff at Cruz is even more absurd. Their columns have never missed an opportunity to promulgate even the most absurd and fact-free arguments for dismantling Obamacare—a moniker that the board on Monday took credit for inventing. Johnson has called Obamacare “the greatest assault on freedom in our lifetime.”