When you watch the event itself, it's hard to tell if Mitt Romney's grim stiffness is a function of his natural self-control or of what was about to happen. It's hard to watch it outside of the context of what's happening now, of course, which colors the whole event. When Donald Trump steps up to a podium that says "TRUMP" in capital letters and starts to talk about how much trouble the economy is in, it seems natural.

And then he endorses Mitt Romney for president.

"There are some things that you just can't imagine in your life," Romney says, after Trump hands it off to him. "This is one of them." Romney, like Trump, is gracious; the whole thing only lasts a minute.

When it happened on Feb. 2, 2012, the endorsement itself was a fairly big deal. Republican candidates had been trekking to Trump Tower seeking the real estate mogul's endorsement for months; Romney first visited the previous September. The day before Trump backed Romney, Newt Gingrich was telling his supporters that Trump was about to back him. Gingrich was actually leading Romney in the national polls at that point, on the strength of his win in South Carolina a few weeks beforehand. Then Romney landed the fish.

Stuart Stevens, a senior Romney strategist in that cycle, says that the moment wasn't particularly noteworthy to the campaign. It happened mostly because the Nevada caucuses were looming and Trump was a major employer in the state. "It was not a big deal," Stevens said when we spoke by phone this week. "Donald Trump's going to endorse, and we're in Nevada. Great. It's kind of a no-brainer.”

Trump's flirtation with a candidacy in 2011 was largely marked by his questioning of Barack Obama's birth status, eventually rendering him somewhat toxic in the public eye. Romney's campaign likely also downplayed the endorsement because of that perception. On Feb. 2, mittromney.com featured blog posts about endorsements from Asa Hutchinson and the governor of Utah. Trump's didn't earn a mention.

When that event ended, so too did Donald Trump's power in the 2012 election cycle. It's easy to see, looking back, how a little less birtherism and a less-savvy nominee could have given Trump a year like the one he's having now. But the apex wasn't a polling run like he's had over the course of 2015. It was that short, too-smiley event in Las Vegas.

In April of 2011, Donald Trump sat down for an interview with, of all people, Meghan McCain. Trump wasn't a candidate, but he was still viewed positively. A Gallup poll that came out at about the same time as the interview had Trump tied for the lead with Mike Huckabee, three points ahead of Romney.

"I like you. I see you a lot on television. I like you and I like your father, I’ll tell you," Trump said to McCain, prompting an equally generous response: "I’m at home in Arizona right now, and I told my mom I was interviewing you, and she was like, 'I think he can really do this.' "

The interview covered remarkably familiar territory. Here's a chunk that could just as easily have been from right before his announcement this year.

Well, the polls have been very gratifying. One of the pollsters actually said to me that my numbers would be better — and I’m leading in just about every poll — if people thought I was going to run, because a lot of people don’t think I’m going to run, and they think it’s because of "The Apprentice."
And I say, give me a break! "The Apprentice" has very high ratings. I don’t need this to get ratings. It’s already the top show on NBC. You understand that. So I think I resonate because I do get along really well with people.
For instance, I spoke in front of the tea party over the weekend in Boca Raton, Florida, and they were expecting 250 people, and when it was announced that I was going to speak they had 6,000 people. I think the reason that it’s resonating is because I say it like it is. China is ripping off this country to the tune of $300 billion this year! They don’t build product as good as we build it, but their currency is so manipulated that it’s very hard for our companies to compete.

Of course, he and McCain also talked about the birth certificate. It was to 2012 what the border wall is to 2016: the foundational obsession. "When I mention why doesn’t he show his birth certificate," Trump whined, "the press kills me! It’s unbelievable! But I keep mentioning it."

He did, to his detriment. The birth certificate wasn't the political winner that illegal immigration claims are now. And about a week after that poll, President Obama unleashed a staggering three-punch combo: He released his birth certificate, mocked Trump at the White House Correspondents' Dinner — and then revealed that during the same timeframe that he authorized the mission that killed Osama bin Laden.

Obama managed to do what critics of Trump's immigration comments this year haven't: He made Trump look foolish. By the middle of May, Trump was polling at 1 percent. He declined to run.

He wasn't done with the cycle yet, though. His endorsement still held some value, as the repeated visits from contenders made clear. And by the end of the year, Trump had wrangled a position moderating one of the dozens of debates to which 2012 Republicans were subjected. This one, hosted by Newsmax, was scheduled to happen on Dec. 27. "Mr. Trump’s role in the debate, which will be broadcast on the cable network Ion Television, is sure to be one of the more memorable moments in a primary season that has already delivered its fair share of circus-like spectacle," the Times wrote then.

It never happened. Trump's involvement doomed it, in part because Trump then, as now, was making noise about a possible independent bid. But it was also okay to dismiss him. Ron Paul called it "beneath the office of the presidency" to attend a debate with a reality television star. Jon Huntsman also declined, telling Fox News that he was "not going to kiss [Trump’s] ring, and I’m not going to kiss any other part of his anatomy." Gingrich had fewer qualms, visiting Trump at Trump Tower a few weeks before the debate was supposed to happen and prompting some establishment hand-wringing.

Trump cancelled his appearance a few days later, in mid-December, saying in a statement that attendance was down thanks to pressure from the Republican brass. But in classic Trump fashion, it was presented as being no skin off his nose. "I am not willing to give up my right to run as an independent candidate," he said. "Therefore, so that there is no conflict of interest within the Republican Party, I have decided not to be the moderator of the Newsmax debate. The American people are embarrassed by the gridlock currently taking place in Washington. I must leave all of my options open because, above all else, we must make America great again!"

(Emphasis added.)

Romney lost Iowa by a hair in early January and won New Hampshire by a wide margin the next week. Gingrich took South Carolina and Romney beat him by a decent amount in Florida on Jan. 31. The Trump endorsement might have been aimed at bolstering Romney's fate in Nevada, but it didn't really need to be bolstered; he won by a wide margin. It was probably more useful in snatching a however small a victory out of the grasp of the surging Gingrich. From that point until the end of the race, Gingrich only won one other state. Trump's public role in the Romney campaign was all but nonexistent (though he did host some fundraisers).

Then, Trump took one more stab at relevance.

Shortly before the Republican convention that August, Trump tweeted a teaser about something he had planned.

It took very little time for people to figure out that the surprise was Trump "firing" Obama, especially after an Obama impersonator posted a photo of himself with Trump on Facebook. And that's exactly what it was.

It never aired. The Republican convention was postponed for a day due to the expected arrival of Hurricane Isaac — a postponement that proved unnecessary. But the newly compressed schedule meant that some things had to be cut, and Trump's surprise ended up on the cutting room floor. It's safe to assume that few in the Romney camp were terribly upset at its loss.

Trump played his hand badly enough in 2012 that any of the staff at his casinos would have been happy to see him sit down at their table. His message wasn't significantly different than it is now, save the birth certificate obsession. But in the end, his Trump card was just that: His name and stamp of approval. Once he finally played it — and Romney awkwardly accepted it -- the game was over.

For a few years.