One moment, we were watching a property magnate, with one eye on the presidency, the other on his reality TV show ratings, puffed up like a bullfrog, rejoicing on an airport tarmac in New Hampshire that America's president of two years had finally made public his birth certificate.
The next, US TV networks interrupted their schedules to cut to the White House, where that self-same president appeared to confirm the momentous fact: not that Barack Obama had indeed been born, but that the happy event indeed took place, as no sane person had ever doubted, on the unimpeachably American soil of Hawaii, one August evening in 1961.
Of late, however, America has seemed to be taking leave of its senses. A quarter of the population, polls showed, and close on a half of Republicans, still refused to believe that unassailable fact.
Yesterday, in a bid to finally close the discussion, the White House released Obama's original 'long-form' birth certificate, rather than the computer-generated duplicate with which the world thus far has had to make do.
It is signed by his mother, the doctor who delivered him and the local registrar.
The document bears witness that Barack Hussein Obama was born to Stanley Ann Dunham and Barack Obama Senior at 7.24pm on August 4, 1961, at Kapiolani Maternity and Gynaecological Hospital in Honolulu, Hawaii's capital city.
The "birther" controversy -- in other words, the contention that the 44th president had, in fact, entered this world in Kenya or Indonesia and that the Hawaii business was a conspiracy -- has moved to the lunatic centre of American political debate.
And no one has done more to propel it there than Donald Trump.
Forced to react to that change, the president yesterday expressed the hope that the matter would now be laid to rest.
He had watched "puzzled and bemused", he said, at how the issue had persisted, in defiance of all good sense.
But the final straw, at least in Obama's telling, had come a couple of weeks ago when he delivered a major speech on deficit reduction, as argument raged over how to tackle the national debt that threatens to squeeze the life out of the worldis largest economy.
And what, he asked, was making headlines next day? The "birther" question, of course.
"Normally I wouldn't comment on something like this," Obama declared. But crucially serious problems confronted the country, and: "We don't have time for this kind of silliness."
Nothing would be done "if we just make stuff up, pretend facts are not facts and get distracted by sideshows and carnival barkers".
The release of the document, which has briefly seemed as pivotal to the existence of the republic as the US Constitution would, Obama hoped, lay the dispute to rest, except for a tiny minority who would never be convinced. "We live," he concluded, "in a serious time."
But do we really? Up in New Hampshire (just by coincidence, of course, the scene of the country's first presidential primary 11 months hence), the carnival barker par excellence claimed Obama's announcement as a colossal victory for himself.
"I am really proud. I am really honoured," Trump proclaimed.
"I feel I've accomplished something really, really important that no one else was able to do.
"I am really happy this has taken place. We have some issues that are unbelievably important."
Whether, however, this triumph will see "the Donald" addressing momentous matters like the deficit remains to be seen.
Why hadn't Obama produced the certificate back in 2007 and 2008, when Hillary Clinton's presidential campaign was asking for it, he pondered.
And even now, he mused, puffing his chest: "We have to look at it. Is it real? Is it proper?"
And if the rigorous Trump is at last satisfied that Obama was not born outside America -- and thus disqualified from being president -- other possible deceptions loom.
"I've heard he wasn't a very good student at Occidental (College in Los Angeles, attended by Obama between 1979 and 1981) but he ended up getting into Columbia (University in New York City) and Harvard.
"How did he do so, if he wasn't a very good student?"
But even if Trump's goal is not the White House, but a new season on NBC for 'Celebrity Apprentice', in American politics right now he is rather more than a sideshow.
CNN was quick to squash a Trump claim yesterday that a poll by the cable network showed him running level with Obama in a hypothetical general election match-up.
No such poll had ever been taken, a CNN anchor declared. Others have been, however, by various news organisations, which put the property tycoon and relentless self-promoter near the top of the Republican field.
Everyone is familiar with Trump's name, and he promises a decision on whether to enter the race at the end of next month.
The likes of Tim Palwenty, Michele Bachmann and Rand Paul would kill for such celebrity right now.
Some, though, ask whether Obama might have done better by keeping the "birther" issue alive a little longer.
Its very existence suggested that Republicans were indeed a party of extremists, they note, driving away the independents and centrists needed to win in November 2012.
None other than Karl Rove, who plotted George W Bush's two White House victories, has said that Trump's obsession with the "birther" issue "means he's off there in the nutty right".
At moments like yesterday, however, you could believe that everyone's gone nutty.