It doesn’t happen often, but once in a great while, videos that don’t exist can cause a stir. In 2008, for example, a variety of far-right activists claimed they saw footage of Michelle Obama referring to white people as “whitey.” The video was fictional – the conservatives who made the claims were lying – but the chatter surrounding the made-up story grew pretty loud.

More recently, Republican presidential hopeful Carly Fiorina falsely claimed she’d seen an abortion-related video that does not, in reality, exist. Pressed for an explanation, Fiorina simply dug in, stubbornly pretending fiction is fact.

And this week, as Rachel noted on the show last night, we’re confronted once more with a high-profile Republican trying to make an offensive point by pointing to footage that exists only in the world of make-believe.

At issue are imaginary reports from 9/11 that Trump believes show “thousands and thousands” of Jersey City residents of Middle Eastern descent cheering when the Twin Towers fell. The Republican frontrunner initially made the claim late last week, but he’s now repeated it and defended it several times since – pointing to news coverage Trump claims to have seen, but which remains entirely imaginary.

[I]n a sign the campaign and Trump himself may be at least a little concerned about the way his comments are perceived, the Donald made an impromptu call to NBC News Monday afternoon. Offering reassurance that he had indeed seen video of the celebrations on television on and “all over the Internet,” Trump said, “I have the world’s greatest memory. It’s one thing everyone agrees on.”

Trump even asked for news organizations to apologize to him for fact-checking his made-up claim. “Many people have tweeted that I am right!” he argued on Twitter, as if this were persuasive.

Making matters slightly worse, Trump’s obvious nonsense was also briefly endorsed yesterday afternoon by one of his GOP rivals.

Dr. Ben Carson apologized for asserting the widely discredited allegation that thousands of American Muslims had celebrated the 9/11 attacks in New Jersey. He told NBC News on Monday that he’d been thinking of celebrations captured in the Middle East – and not New Jersey. Adding his voice to claims most recently made by Republican front-runner Donald Trump, Carson told reporters twice on Monday that he’d seen the “film” of the celebrations. When asked by NBC News specifically if he meant in New Jersey, he replied yes. Later on Monday, his campaign began walking back the comment.

We’ve reached a very strange point in American politics. A candidate for the nation’s highest office is seen as having done something halfway admirable because he’s acknowledged a misstep in which he confused New Jersey and the Middle East.

As for Trump, NBC News’ Katy Tur asked the New York Republican yesterday, “Where did you see the video? We can`t find anything in our archives. Others can`t find anything in theirs.”

Trump replied, “I saw video. It was on television. How would I know? You`ll have to find it. I`ve also seen it all over the Internet. I`ve seen it on the Internet over the years. I`ve seen it on the Internet.”

Actually, no, he hasn’t, because the video does not exist.