The energy in the convention room as Ted Cruz began to speak Wednesday night was weird, at least from where I was sitting high among the alternate delegates. They seemed as if they had read that people get excited at conventions and were trying to mime the appropriate responses but weren't quite able to pull it off.

They roared at lines about abortion, guns and building a wall on the Mexican border but otherwise seemed curiously subdued — clapping, but not as much as I'd expect at a speech that basically consisted of Cruz ripping off chunks of raw steak and tossing them to his conservative audience.

It was only at the end of the speech that I understood what I was seeing. As Cruz talked about voting to uphold the conservative principles that he'd just spent the past minutes outlining, the crowd around me grew enthusiastic. "How odd," I thought. "I'd have thought they'd be angrier about his refusal to endorse Trump."

"Ah", I said to myself, "they don't realize it. Cruz has masterfully convinced them, with carefully phrased weasel words, that he is endorsing, even though he has not come even close to doing so."

I was wrong. Both the earlier flatness and the later applause were explained by the same thing: They were waiting for a Cruz endorsement that never came.

I made the cardinal mistake that afflicts all writers from time to time: I forgot that other people don't know everything I know. I walked into the room on the third night of the Republican National Convention certain that Ted Cruz was not going to endorse Donald Trump because that was the consensus of all the news coverage. The delegates, on the other hand, were not refreshing their news feeds with the alacrity of a lab rat pushing one of those levers that dispense cocaine. They took Cruz's presence as a sign that he was going to rally around and endorse Donald Trump for the sake of party unity and of beating Hillary Clinton in the fall.

When it finally became clear that no endorsement would be forthcoming, they turned on him in rage. The boos and demands for endorsement filled the arena with an angry roar. Heidi Cruz was reportedly escorted from the floor by security; her husband would later be accosted by a livid delegate who called him a traitor. Meanwhile, up in my section, outraged alternates said, over and over, that if he couldn't endorse, he shouldn't have come.

The mistake made by the alternates is understandable. The mistake made by Ted Cruz, and especially, Donald Trump, is not. Somehow these two former rivals faced off over the convention floor, and both lost.

Cruz's supporters may view this as a bold and principled stand that will position him well for 2020 as the conscience of the party. Bold and principled it may be, but after hours of reflection, I still can't see how this does anything but hurt him. A whole lot of Republicans — including a whole lot of true-blue base conservatives who are Cruz's natural home in the party — want the party to come together to defeat Clinton.

That clip of Cruz getting booed by his own party convention is now the highest-profile moment of his career. It will play over and over for the next four years, and possibly beyond. Watching it, I couldn't help but think of a story I once heard about a politician who had been captured on film being chased by his own angry constituents. Allegedly, the politician asked a staffer when the media would stop playing the clip; allegedly, the staffer replied, "Sir, they'll play it when you die."

Of course, Cruz has built his career on such high-profile moments. But his photogenic stands on the Senate floor were stands against Democrats, and Democratic programs, not against the fellow who won his own party's primary.

I continue to think that the NeverTrump Republicans are a sizeable group; I don't think that they are, by themselves, sizeable enough to constitute anyone's political base. For many other Republicans, this will finally make plausible what that Washington establishment has been saying for months: that Cruz is an opportunist who is willing to badly hurt his own party for the sake of some imagined political advantage. When they make that charge again in 2020, it will have a much more receptive audience.

For somewhat similar reasons, I don't see how this redounds to Trump's benefit. It's going to be difficult — I'm tempted to say "impossible" — for Trump to play this as yet another example of the hated establishment trying to stop the Trump Train. Cruz's speech was pure red meat, and his base is the tea partiers, not Washington insiders.

The debacle that unfolded in prime time will highlight, not how he's overthrowing the establishment, but how badly Trump has divided the party he claims to represent. More importantly, this marks yet another convention news cycle when Trump should have been presenting himself to the American people and reaping the poll bump that inevitably follows. Instead, the news is dominated by a negative story about Republicans sniping at one another.

Trump's running mate, Indiana Gov. Mike Pence, and Wisconsin Gov. Scott Walker both gave very effective speeches, which will be drowned out by the story of the Trump-Cruz feud. It's hard to comprehend why Trump allowed Cruz to give a prime-time speech without securing a promise of at least a tepid endorsement.

Media reports are saying that Trump knew this was coming days in advance. Yet the campaign not only allowed the speech to go forward, but may even have actively whipped up the boos rather than encouraging followers to smile and pretend there was an endorsement somewhere in Cruz's tangled verbiage. If true, that means Trump's staff either somehow thought that this debacle would rebound to his benefit, or, even worse, that they were more intent upon punishing Cruz over a personal slight than presenting a positive and unified face to American voters.

For reporters, this has been the most exciting convention to cover in decades. For the rest of America, it's been a pretty sorry spectacle. Worse still, almost all of its errors have been unforced, the rookie mistakes of a campaign that is inexperienced and understaffed. Conventions are supposed to be coronations. What Trump has instead shown the country is a power vacuum at the center of his party — one that threatens to consume his presidential hopes.