On the one hand, Speaker Paul Ryan’s announcement on CNN Thursday afternoon that he cannot yet support Donald Trump for president was a gesture that took guts.

Ryan broke with Republican National Committee chair Reince Priebus and Senate Majority Leader Mitch McConnell. Ryan also broke with many of his own constituents: while Sen. Ted Cruz (R-TX) won the first congressional district, Trump won Ryan’s home town of Janesville and all of Kenosha County in the Wisconsin primary.

On the other hand, Ryan’s surprise came after he had pledged, in January, to support Trump if he were indeed the eventual nominee. It also came as Ryan is preparing, as the presumed chair of the Republican National Convention in Cleveland in July, to preside over a voting process that is expected to elect Trump on the first ballot.

Ryan also chose to question Trump’s conservatism on a mainstream media network, rather than in a conservative forum.

The result: Ryan has raised doubts about Trump — but also about whether he should preside in Cleveland.

Under Jake Tapper’s mild questioning, Ryan seemed to back away from the essence of what he was doing. “I’m just a guy,” he said. (Tapper reminded him that he is also Speaker of the House.)

But Ryan’s decision to withhold his endorsement is, as CNN’s Dana Bash later observed, “seismic.” It has re-opened fault lines in the Republican Party, just as the “Never Trump” campaign seemed to be fading into irrelevance.

Ryan implied that Trump could still earn his backing by showing his commitment to conservative principles, and by changing the tone of his rhetoric.

But that is a definite shifting of the goalposts — and he did not need to go on The Lead with Jake Tapper to convey that message.

Moreover, by creating new ideological hurdles for Trump , Ryan risked reviving questions about his own ideological purity, and the kind of divisive internal battles that emerged over the budget deals he recently struck with the Obama administration.

The same applies to questions of tone. While Ryan delivered his message on CNN in typically a civil, almost apologetic way, it was still a stab in the back, however polite.

And CNN’s Tapper was eager to oblige. When Tapper asked his panel to react to Ryan’s announcement, they had only seen half the interview, as Trump supporter Kayleigh McEnany pointed out. It was mildly unprofessional, and seemed almost set up to maximize damage to Trump and to embarrass his supporters.

Viewed in the best light possible, Ryan’s gesture can be seen as an effort to insulate the House of Representatives — and his own Speakership — from the anticipated negative electoral consequences of having Trump atop the ballot in November.

He may, however, provoke the opposite result. Many Republicans will not look kindly on the Beltway rejecting their choice, especially after primary voters pronounced their grim verdict on Ted Cruz’s efforts to use the delegate system to override millions of ballots.

If Ryan does not want to do the difficult work of unifying the party, he has a simple alternative: he can recuse himself from chairing the convention. Then he can give full voice to his doubts about Trump.

There is, as he well knows, a difference between running a think tank and running a political party. And politics requires hard choices. Pundits may take false comfort in a futile third-party option. Ryan does not have that luxury.

Since he emerged as a national leader in the conservative movement, Ryan has stood for high principles and civility. The danger is that Ryan may have undermined his support among the party base, such that he will struggle later to put his worthy ideals into practice.

And the tragedy is that his message to Republican voters Thursday, while delivered in civil tones, was decidedly uncivil: it was a rejection of the voters’ will, and invites conflict in Cleveland.

Thankfully, for once, Trump chose not to escalate. But how much more of this can the GOP endure, and survive?

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. His new e-book, Leadership Secrets of the Kings and Prophets: What the Bible’s Struggles Teach Us About Today, is on sale through Amazon Kindle Direct. Follow him on Twitter at @joelpollak.