A seminal moment in the nation’s 58^th presidential election is guaranteed three weeks from today.  

All 247 Republicans in the House of Representatives will have their first and only opportunity to gather in the same room , at the same time, to size up Donald J. Trump before he stands for nomination as the most temperamentally and politically unorthodox person ever put forward by the GOP – or any other mainstream American political party.  

For these politicians, who can fairly be described as the largest single bloc of the national Republican establishment leadership, it will be their single collective shot at altering Trump’s extraordinary trajectory.  

No matter what happens behind those closed Capitol doors on July 7, it will stand as an enormously important moment for the party system in general and for the GOP in particular. And should Trump make it to the White House, his first encounter with his adopted party’s entire congressional rank-and-file could be remembered as a turning point in his policy-making relationship with the Hill and as a predicate for an almost guaranteed struggle over the balance of constitutional powers.  

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Trump to Meet With House July 7

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In essence, the lawmakers must choose to embrace one of two starkly different personalities — profile in courage or passive milquetoast.  

They can confront Trump with unambiguous and unified anger and aggression, vowing to disavow his candidacy en masse unless he categorically and immediately abandons his tempestuous, nativist, divisive, ideologically erratic and fascistic-sounding rhetoric in favor of themes that are both consistently conservative and consistent with the standards for a leader of the globe’s only democratic superpower.  

The alternative is to permit this singular moment for assertiveness to pass them by, which will commit House Republicans for the rest of the campaign to acquiescing in Trump’s unprecedentedly inflammatory way of being.  

That’s what will happen if the lawmakers offer a diffuse mixture of plaintive admonition, pleading encouragement and advice about the benefits of Trump making good on his long-promised pivot toward acting presidential.  

The former approach would amount to an unprecedented repudiation from inside Congress of a putative nominee, and that could open the door to a viable if extremely-late-germinating effort to prevent Trump’s coronation at the convention in Cleveland just two weeks later.  

Even if that didn’t pan out, GOP members would still enter the fall campaign with their political identities as clearly separate as possible from their standard-bearer.  

So if Trump got swamped in November, their chances for survival would be unusually disconnected from his fate. They could say they survived or fell with their consciences clear. And those who prevailed would have the moral and political standing to launch the latest rebuilding of their party.  

Finally, if Trump managed to win the presidency, he’d show up for the inauguration in January knowing he could not simply dictate the terms of his conversations with an almost certainly solid House majority.  

The alternative GOP approach — remaining on the passive-aggressive path of least resistance — could have inverse consequences that are at least as consequential.  

Trump could plausibly arrive at the Quicken Loans Arena proclaiming himself conqueror of the old order and leader of a new and unified mainstream. The members who stayed silent or stayed away would have no credible opening for renouncing him. They would be lashed to his coattails for better or worse.  

If he lost, they’d be undeniably complicit in the party’s third consecutive national failure and would have little credibility to claim it’s their right or responsibility to orchestrate the next GOP restoration.  

[Trump, Ryan Shock with Good Vibes ]  

If he won, the members re-elected alongside him would start the 115^th Congress as little more than bovine chattel, politically powerless to push back when Trump either ignored them through his bullying assertions of executive authority or corralled them to get behind his unpredictable legislative program.  

Speaker Paul D. Ryan transformed himself two weeks ago into the leader of the resigned and the accepting, shedding the mantle of political bravery just a month after declaring the newly presumptive nominee was a long way from deserving a House leader’s endorsement.  

Now Ryan’s tortured and politically half-pregnant approach – denouncing Trump’s behavior on a regular basis while asserting his endorsement is locked in place – has become the default setting for the entire House Republican Conference.  

Outside the GOP cloakroom and in the Speaker’s Lobby these days, the construct used by so many back benchers sounds remarkably similar. They do not approve of many things Trump says or how he says them, but they support him as the fair-and-square winner of the nomination. They profess grudging acceptance of the sinner alongside disappointment in his multiple sins.  

If that groupthink is to be altered in time to change the course of Republican history, it must happen in time for Trump’s next visit to Capitol Hill — which, by the way, will be the first time many lawmakers get to lay their own eyes on the outsider real estate tycoon.  

It’s a long-shot bet that a 70-year-old businessman will suddenly decide to promise, in front of dozens of people he’s never had any dealings with, that he’ll reinvent himself by repudiating the very personality that just propelled him to such rapid and unlikely prominence in the American power dynamic.  

The timing of the House GOP caucus (Senate Republicans have announced no similar gathering) is propitious. Members will have a couple of days for huddling to get their story straight after returning from the July Fourth break. And that recess will provide an entire week for assessing the level of buyer’s remorse among the 13.6 million (44 percent) who voted for Trump in the primaries and caucuses.  

There is one thing — losing — that many Republican congressmen disdain far more than having a party leader who’s increasingly labeled as racist, misogynistic, unstable and an ideological chameleon. Depending on whether they conclude his candidacy is survivable, in the next three weeks they’ll have to come up with their final answer for when their grandchildren someday ask:  

“Where were you when Donald Trump stood for president, on the side of the angry mob or on the arc of history bent toward righteousness?”