Andrew Harnik / AP

Paul Ryan and Mitch McConnell didn’t have a whole lot to say on Wednesday, a day after Donald Trump became the presumptive standard-bearer of their party.

You’ll have to forgive them if they needed some time to cope; their dream of enacting the conservative agenda that has been a bedrock of Republican policy for a generation might well die with Trump’s nomination.

Trump is undoubtedly a short-term political threat to Ryan, the House speaker, and McConnell, the Senate majority leader. His unpopularity with the general public could drag down Republican congressional candidates across the country, hand control of the Senate and maybe even the House to Democrats, and cost both men their august job titles. But the bigger and potentially more durable threat that Trump poses to Ryan and McConnell is what his nomination means for the conservative vision of government that they have been pitching to Republican voters, activists, and donors for the last eight years. Just wait until 2017, they’ve pleaded: With a conservative partner in the White House, Republicans would be able to enact the deep spending cuts, entitlement reforms, tax overhaul, and repeal of Obamacare they’ve long dreamed of.

With Trump—let alone Hillary Clinton—at the country’s helm, much of that agenda would become moot; a dream deferred for at least another four or eight years.

Consider the apostasies of the Republican nominee-in-waiting:

Ryan has made his career out of proposing dramatic reforms to Medicare and Medicaid, arguing that they must either be partially privatized or block-granted to the states to save them for future generations. Trump has shot down these ideas in language that could be taken straight from the lips of Nancy Pelosi.

Ryan and McConnell have both been championing free-trade policies for years and criticized President Obama for dawdling on striking international-trade deals early in his term. Trump’s opposition to pretty much every trade accord of the last 25 years is now a centerpiece of his economic platform. His nomination may be the death knell for the Trans-Pacific Partnership, for which both Ryan and McConnell have long advocated.

Ryan has been a leader in the camp of congressional Republicans that has pushed for comprehensive immigration reform, including a path to legal status—if not citizenship—for undocumented immigrants. McConnell is more hawkish on immigration, but like Ryan he is adamantly opposed to Trump’s call to deport millions of people or ban Muslims from entering the United States.

On foreign policy, the two Republican leaders have been staunch internationalists; they strongly supported the Iraq War and have argued in favor of U.S.-led interventions during both the Bush and Obama administrations. Trump has said that he, like Obama, opposed the Iraq War from the start. He slammed President George W. Bush for allowing the 9/11 terrorist attacks to occur on his watch. And he recently called for an “America First” foreign policy under which the United States would threaten to withdraw support from NATO if its allies did not pay for their own defense.

Trump is not at odds with conservative doctrine on every issue. He wants to repeal Obamacare and replace it with more market-centered reforms. While he has campaigned as a populist, his tax plan skews toward the wealthy and is similar in structure to what Republicans have long proposed. And some Republicans argue that because he has shown so little interest in policy specifics and prides himself on being a non-ideological dealmaker, he would be a willing partner to congressional Republicans who could deliver him legislative victories. Ryan in particular has pushed the House GOP to develop a substantive policy agenda that would be neatly packaged for the party’s presidential nominee to pick up and campaign on in the fall. Trump, however, has thus far shown little interest in taking his cues from Capitol Hill.

Beyond all of this, conservatives must face an even scarier possible conclusion about Trump’s success. What if the conservative platform that congressional leaders like Ryan and McConnell have long advocated was never all that popular with rank-and-file Republicans? Conservative lawmakers in Congress have assumed that however much Democrats demonize Republicans for trying to slash spending and entitlement programs, cut taxes, and pursue free-trade policies, at least that agenda unified and excited the conservative base. Trump’s nomination, however, seems to blow up that claim.

In terms of conservative orthodoxy, Trump stood apart from nearly all other Republicans who sought the nomination, and especially his final major rival, Ted Cruz. For all the hatred Beltway Republicans directed at Cruz, little of it had to do with policy. They disliked him personally and disagreed with his never-compromise mantra, but a Cruz presidency alongside a Republican-led Congress might well have led to a conservative transformation of federal policy.

This is not likely under a President Trump. For movement conservatives, the most charitable analysis of the Republican nomination fight is that conservative policies weren’t rejected because they just weren’t represented on the ballot. “This election was less about specific issues than it was about personalities and attitudes,” said Doug Heye, who served as a top adviser to former House Majority Leader Eric Cantor.

As Trump assumes the mantle of presumptive nominee, the GOP establishment as a whole is deciding what to do. Some are singing dirges, and others, like the Republican National Committee chairman Reince Priebus, are falling in line. Ryan and McConnell have vowed to back the nominee, no matter how repugnant they find his views or his rhetoric. On Wednesday, however, they said little. Ryan said nothing at all, while late in the day McConnell issued a terse statement backing Trump that was notable only for its utter lack of enthusiasm. “As the presumptive nominee,” McConnell said, Trump “now has the opportunity and the obligation to unite our party around our goals.” The two GOP leaders are undoubtedly contemplating the political impact of a nomination they could hardly have imagined would actually come to pass. Their lamentations must surely extend to policy, and a conservative governing agenda with a future that has rarely seemed more in doubt.

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