Reactions to the Federal Bureau of Investigation search of Mar-a-Lago revealed a symmetry between Donald Trump’s loudest supporters and his loudest detractors that either side want to ignore: the need to keep away from acknowledging their unpopularity and taking accountability for his or her decisions.

Mr. Trump’s supporters have supplied a stream of theories to justify their perception that he didn’t lose the 2020 election—voting machines have been tampered with, election officers have been corrupt, poll bins have been stuffed, and so on.