His fervent, dayslong pushback has displayed not only his prolonged focus on a personal spat but his willingness, notably again late on Thursday, to deploy government staff and resources to justify an inaccurate claim. Presidential proclamations can move markets, rattle world capitals and, in this case, unnecessarily alarm the residents of a state. Trump’s relationship with the truth and accountability threatened to, yet again, diminish the weight of any president’s words…

Trump has owned up to a few mistakes: He apologized, once, for the Access Hollywood tape that captured him boasting about groping women — though he later mused that the audio might be fake. And the mistakes he has made in office were, by his account, the appointments of officials who have let him down, like Federal Reserve Chairman Jerome Powell and Attorney General Jeff Sessions.

His attitude is no joke to those who worry about the potential consequences when the matter is far more grave than a weather map.

“The Constitution, with its checks and balances, was drafted on the intellectual foundation that we all make mistakes all the time: a president does, Congress does, the courts do, the people do,” said Meacham. “It’s remarkable that more harm hasn’t come of it. It would be funny if it weren’t so serious.”