Here is one thing we are reminded of over and over about President Trump: The man simply cannot help himself — especially when cornered. Given one more chance to forcefully condemn the neo-Nazis and white supremacists whose rally in Charlottesville, Va., ended in violence and a counterprotester’s death, Mr. Trump angrily insisted, as he had suggested on Saturday, that both sides were equally to blame — a false equivalency that not just his critics but also an increasing number of his supporters have urged him to abandon.

The setting was a bizarre and contentious press conference at Trump Tower in Manhattan that was originally meant to be about infrastructure but quickly escalated into a shouting match about Charlottesville. Gone was the measured tone that the president’s aides had talked him into on Monday, when he said “racism is evil” and appeared to distance himself from his earlier claims about shared responsibility for the violence. In its place was a high-decibel defense of his original position, to which he added the claim that while there were “bad people” and “very fine people” on both sides, the “very, very violent” protesters on the “alt-left” who came “charging in without a permit” were at least as culpable as the neo-Nazi protesters.

In so doing, Mr. Trump took up many of the talking points of the white nationalists and far-right activists who have been complaining that the news media and the political establishment do not pay enough attention to leftists who call themselves anti-fascists. He also sympathized with the demonstrators’ demand — the announced reason for their rally — that Robert E. Lee’s statue in a Charlottesville park be saved. “Is it George Washington next week? And is it Thomas Jefferson the week after?” However deep their flaws, though, Washington and Jefferson are memorialized as heroes of American freedom, whereas Lee symbolizes violent division. It was hardly a surprise, then, that David Duke, the former Ku Klux Klan leader, tweeted to thank the president for his “honesty & courage” in denouncing “leftist terrorists.”