The much-anticipated appearance of Ted Cruz at the Republican National Convention turned out to be everything people anticipated — for better and worse. The runner-up for the GOP ticket delivered a powerful speech in defense of conservative principles after congratulating Donald Trump for winning the nomination. The crowd seemed to fall under his spell, and Cruz threatened to capture the evening. However, when he tried to deftly avoid a direct endorsement, Cruz angered the crowd, which booed him as he left the stage:

Joe Scarborough diagnosed this succinctly:

Had Cruz never mentioned voting at all, he likely would have finished up without provoking the response. In this case, though, “vote your conscience” was doubly provocative given the sturm und drang the last two days over Rules Committee reports. Instead, he made his non-endorsement a little too specific, and the delegates turned on him.

It’s too bad, because this was a good speech, and delivered in particularly good form. Cruz dispensed with the preaching style that he had adopted during the campaign, and went back to his normal rhetorical style. It was effective, right up until he got “too clever by half,” as Scarborough said.

Cruz’ supporters cheered him for his principles, but let’s not kid ourselves. One reason why Cruz — or someone else — isn’t speaking tomorrow is because Cruz often backstopped Trump on the campaign trail. He’d hoped to convince Trump supporters to back Cruz when they realized that Trump wasn’t a serious candidate. As late as January, Cruz was calling Trump a “good man,” even though Trump had repeatedly aimed personal attacks on other candidates that foreshadowed the ones Trump launched at Cruz’ father and wife. Cruz also pledged to back the nominee during the campaign when the pledge was aimed more at Trump to keep him from playing dog-in-the-manger if he lost. Cruz gave a terrific defense of conservative principles, but his refusal to endorse while calling for “party unity” at the same time isn’t exactly a principled stand.

Newt Gingrich, who followed shortly afterward, skewered Cruz a bit by claiming to divine what he meant by “vote your conscience.” Gingrich told the crowd that Cruz had said that in the context of protecting the Constitution, and since Hillary Clinton will shred it as president, then the only way to “vote your conscience” is for “the Trump-Pence ticket,” QED.