John Kasich waving good-bye to his presidential hopes as he leaves the stage in Detroit last night.Jim Young / Reuters

Those seconds come in the segment from last night’s debate that you see in the YouTube video below, where Kasich answers the question asked of each of the four surviving candidates: will you support the Republican nominee, no matter what? I.e., even if it’s Donald Trump?

The preceding 24 hours of political history had been extraordinary, as the remnants of the GOP establishment turned in revulsion against Trump. A bunch of foreign-policy eminences, ranging from hawks and neocon hardliners to members of the “realist” camp, put out a statement of “united opposition to a Donald Trump presidency.” The party’s immediately previous nominee, Mitt Romney, who in normal times would still be at least the honorific leader of his side, blasted Trump as a “fraud” and “phony” in a powerful speech yesterday morning. Then in the evening, the first hour-and-a-half-plus of the debate consisted of arguments from Kasich, Cruz, and Rubio about the outrageousness,  unacceptability, phoniness, and clownishness of Trump and what he represents.

Leading up to this moment. Watch—and weep for Kasich’s missed chance.  

(The clip is cued to start with Kasich’s answer, at time 1:40. The whole clip shows you how Cruz, Rubio, and Trump himself dealt with the question.)

John Kasich’s fundamental argument for staying in the campaign boils down to: I’m the sane one. I’m the one with a heart. I’m the one who cares about the actual machinery of legislation. I’m the one who can get something done. The chance to show that he really meant it came with the question, to which he could have said something like:

Look, I’m a loyal Republican. I’ve given my working life to this party, because in the Congress and in the State House I’ve seen what sensible conservatism can mean for our people. The party of Lincoln and of Eisenhower and of Reagan, the party of [fill in the next three lines of “morning-in-Amerca”-ism] has always stood for liberty and opportunity at home, and for strength and dignity abroad.

And it’s precisely because I care so much about those principles, and because I have so much respect for the generations of Republican men and women across this country who have worked so hard to make them a reality, that I will not stand for the hi-jacking and perversion of our party by someone who has just happened upon it as his latest vehicle of convenience, and who represents nothing that Lincoln or Eisenhower or Reagan would support.

Because I care so much for the Republican Party, I will not support someone who is the antithesis of everything it represents. I will work as hard as I can to keep Donald Trump from being our nominee — and I cannot support him as a potential president.

* * *

Look at it this way, Governor Kasich: What do you have to lose? If you say you’ll support Trump, as you just did, then you lose in three ways: Your criticism of him rings hollow; you make it all the more likely that the Trump Express keeps rolling on; and you badly weaken your own case as the sane-Republican’s alternative in some convention-breakdown scenario. You have avoided the humiliation visited upon Chris Christie, in his role as spoils-of-war captive at Trump appearances. But the chance to be the one active candidate who stood against him came—and went.

That sane-Republican role is obviously the one Mitt Romney was auditioning for with his speech yesterday. Yes, critics could unkindly point out (as Trump quickly did) that Romney had been eager for Trump’s endorsement four years ago. But that was then—before the “rapists,” and the Wall, and the Muslim-ban. At least Romney has taken his stand as regards Trump 2016. Alas, you have, too.

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