Memory is a funny thing. Chances are, you still remember clearly what President Trump said in 2017, after violent clashes in Charlottesville between white supremacists rallying around a statue of Robert E. Lee and leftist counterprotesters. “You had some very bad people in that group,” Trump allowed at an Aug. 15th news conference, “but you also had people that were very fine people, on both sides.” Almost three years on, anyone who tries to deny that Trump is a racist is apt to have those words flung back in their face.

We recall those remarks, but most of us have slowly forgotten about what else Trump said, although it was almost as controversial at the time: “So this week it’s Robert E. Lee. I noticed that Stonewall Jackson is coming down. I wonder, is it George Washington next week? And is it Thomas Jefferson the week after? You know, you really do have to ask yourself, where does it stop?”

This came in for much derision. In The Post, Princeton historian David Bell declared that the distinction between slavery-defending Vice President John C. Calhoun and George Washington “is not difficult to make.” Jim Grossman, executive director of the American Historical Association, called the attempt to equate Confederates with Founding Fathers “absurd” and “unacceptable for the president of the United States,” while Douglas Blackmon of the University of Virginia said, “The most kind explanation of that can only be ignorance, and I don’t say that to insult the president.”

Three years later . . . can it be? Trump looks prescient, and his critics perhaps a touch naive. The iconoclasts, having largely defeated the rebel army, are turning on the Founding Fathers. It was supposed to be trivially easy to articulate those distinctions, yet I have not seen a flurry of commentary from historians eager to educate the protesters as they schooled Trump.

Even George Washington University, whose very name constitutes an endorsement of our first president, seems to have quietly removed a bust of Washington for safekeeping after it was toppled from its pedestal, rather than loudly condemn an attack on the father of our country.

In private, most of my left-leaning friends say that Washington should stay. They don’t play down the moral catastrophe of his slave ownership, but they weigh that, as Bell advised three years ago, “against his role as a heroic commander in chief, as an immensely popular political leader who resisted the temptation to become anything more than a republican chief executive, and who brought the country together around the new Constitution.” And they conclude that Washington deserves to stay in the canon of our country’s heroes — deeply flawed, as most heroes are, but still worthy of admiration for the good he did.

They’d just prefer not to have to say that out loud.

Trump is no great moral theorist, but he does have a certain cunning about human behavior, enough, possibly to foresee that the Great Statucide would proceed by what conservative writer Rod Dreher has dubbed “the Law of Merited Impossibility”: Conservatives warning about the dire consequences of some social change are dismissed as hysterical cranks — and then, when exactly what they predicted eventually comes to pass, denounced as bigots for opposing the new order. Implicit in Dreher’s law is an intermediate phase in which a large number of people sit uncomfortably silent as the radicals take the moderate majority’s well-intentioned efforts further than they ever dreamed.

If you had told me 10 years ago that same-sex marriage meant Christian bakers being legally required to bake cakes for same-sex weddings, I, or any supporter of marriage equality, would have dismissed this as conservative propaganda, too silly to even bother refuting. Probably someone did tell me that, at some point; probably I laughed and said, “Come on.”

Then, shortly after the Supreme Court ruled, activists began declaring that of course those bakers had to bake those cakes. Privately, one heard from a lot of same-sex marriage advocates who thought this went too far. But publicly, they found other things to talk about. And so the default position on the left became exactly the sort of thing that everyone had declared would never happen.

What Trump understood, and his critics perhaps didn’t, was that you cannot credibly declare that some revolution in social affairs has a natural stopping point unless you personally commit to stopping it when it goes too far. It’s not enough to say that very clear distinctions can be drawn between allowing gays to marry and forcing people to cater weddings that conflict with their religious beliefs; between the father of our country and the traitor who led a rebel army in defense of slavocracy. When the moment arrives, you have to actually draw them.

If you don’t, you will cede issue after issue to the radicals. And if uou make those tacit concessions again and again and again, then however privately you may rue it, you will nonetheless end up with something very different from your idealistic vision. Something that looks like . . . well, like the Republicans who quietly ceded their party and their conscience to Trump, one outrage at a time.