Well before Republicans officially lost the 2012 election, leaders of the party, along with Mitt Romney’s campaign strategists and countless conservative opinion-makers, understood just how damaging the presidential nominating process had been for them. The gravest damage came from an unconstrained series of 20 debates, which pit candidates against each other in a madcap dash to win the hearts of audiences that booed gay soldiers and cheered at the notion that society should allow uninsured citizens to die.

Along the way, the eventual nominee gained notoriety for an agenda that included privatizing the Federal Emergency Management Agency, squeezing unauthorized immigrants into discomfort until they self-deported, and for offering an underdog a $10,000 bet.

After the election, the Republican National Committee set about sanding off the party’s rough edges. It encouraged Republicans to pass immigration reform and soften their rhetorical tropes, and in so doing repair the party’s relationship with a younger, more diverse segment of the electorate. It also set about tightening the rules governing primary debates—to limit the total number of them, exclude certain networks and moderators, and penalize candidates for circumventing the process. By doing so, the RNC hoped the party could escape its own primary without incurring the self-inflicted wounds it suffered in 2012.

Thursday’s Fox News debate represents the failure of that effort. The RNC, led by Reince Priebus, succeeded only in holding the number of debates to seven, which is still enough exposure time to wash out the kinder, gentler image he wants the party to project.

The complete explanation for the failure is complex, but it stems from the fact that the GOP (partially by design) has become dominated by reactionaries and ideologues, rather than by allied factions amenable to compromise. That explains both Donald Trump’s emergence as a towering Republican figure, and the influence Fox News has over the party. Both of those factors, in turn, explain why Thursday’s debate, and perhaps debates to come, will bear so much resemblance to the 2012 debates Priebus hoped to vanquish.

Fox’s influence has been particularly devastating. Trump isn’t the first flash-in-the-pan candidate to illuminate a party’s dark underbelly. But Fox amplified the incentives he created for other candidates to jockey for attention.

The network’s criteria, which limited the debate to the ten highest-polling candidates, guaranteed that about one-third of them would be excluded. This implicitly encouraged lower-polling candidates—the also-rans of the also-rans—to call as much attention to themselves as possible, in order to secure their place on the debate stage, or in the hope that a last-minute surge would win them one. That has meant trying to outcompete Trump for the limelight—and in just the past several days, we’ve seen candidates compare a multilateral agreement to curb Iran’s nuclear ambitions to the Holocaust (Mike Huckabee), cook bacon on the tip of a semi-automatic rifle (Senator Ted Cruz), and mount a campaign that will result in a government shutdown unless Congress completely defunds Planned Parenthood (Cruz, and Senator Rand Paul).

In the end, Trump’s most vocal critics—Senator Lindsey Graham and former Texas Governor Rick Perry—didn’t make the cut. The stage will thus be overrepresented by people unwilling to attack Trump directly or build a case that he doesn’t reflect the party’s values.

Of course, the whole point of circumscribing the debate process was to keep unpopular values from garnering excessive attention. The Republican Party wouldn’t have gone to such great lengths to intervene if these debates were harmless spectacles. In reality, they’re a proving ground for policy and strategic thinking. They’re where candidates get locked, as they did four years ago, into commitments like never raising taxes on the affluent and voiding popular or high-stakes executive policies on their first days in office.

Republicans didn’t react to losing in 2012 by abandoning shared objectives. But they did put a great deal of effort into changing processes and clamping down on rhetorical excesses, in the hopes of keeping the party from steering in a reactionary direction. But the forces they were trying to control are too great, and they created too much pressure for the GOP to keep the lid on.