This affair serves as the perfect illustration of the ugly manner in which the Trump phenomenon now works. That there is no evidence of “thousands” of American Muslims cheering 9/11 from New Jersey is, frankly, immaterial. Why? Well, because Trump is playing a character on TV, and his script includes no room for error. By the rules he has set out for himself, whatever Trump says he is, he must be. As such, he can’t possibly have misremembered what happened after 9/11 — as might any human being — because he has the World’s Greatest Memory, and the guy with the World’s Greatest Memory doesn’t misremember.

This rule applies consistently. If Trump says he’s a conservative – despite holding positions that usually make conservatives shriek – then he’s a conservative. If that requires redefining conservatism, so be it. If he says he wasn’t mocking a journalist whom he was quite obviously mocking, then he wasn’t mocking that journalist. If that requires his admirers to suspend disbelief beyond all possible limits, then so be it. And if he says that he saw something of which there really is no evidence, then he must have seen it. Worse still: If you like him, then you must have seen it too.

In this late stage, Trump’s whole campaign has become a ghastly feedback loop from which there is no hope of escape.