The Republican Party entered the year with a collective action problem, the problem of Donald Trump. No respectable GOP candidate wanted to take the risk of flaming out, like Rick Perry and Bobby Jindal did, for criticizing Trump too early. So most Republican candidates said nothing — or worse, praised the man they assumed to be merely an ephemeral frontrunner.

Ted Cruz, who last December said Trump is “terrific,” was counting on time and chance to scuttle Trump’s candidacy. He waited too long to attack his rival. Trump repaid the compliments by attacking Cruz’s wife and accusing Cruz’s father of being involved in the assassination of John F. Kennedy. Cruz was left spluttering that Trump was an “utterly immoral” man and a “pathological liar.”

Now the GOP is stuck in paralysis again, unable to organize a convention revolt. They are stuck half-endorsing, half-lamenting a candidate who spreads conspiracy theories, praises dictatorships, and sources Twitter images from anonymous anti-Semites. By doing nothing, well-meaning Republicans hope they can be spared the fallout when Trump loses. But many will simply remember that they did nothing. And there’s always the chance that the real disaster happens, Trump wins, and the party has to half-endorse, half-lament his agenda, his memes, and his scandals for another four years.

A party can survive a broken convention. It may not survive two consecutive bad presidencies. But preventing that requires actually getting up and doing something.