Charlottesville, Virginia will no longer celebrate Thomas Jefferson’s birthday, even though Jefferson lived there. Supposedly this is because Jefferson was a slave holder.

The action by Charlottesville’s city council is the latest event in a national campaign by leftist zealots to erase our historical tradition.

In actions reminiscent of the Taliban’s destruction of historical treasures, the new totalitarians have removed and mutilated statues of Confederate heroes, censored artwork, and replaced monuments to great literary figures like Shakespeare and Kipling with images of ephemeral mediocrities. The excuse for the desecration is that the historical figures being attacked shared faults common in their own times.

But in my view their real purpose is to induce people to forget how great figures in Western history rose above their own times and contributed to human progress.

In a case decided last month, two of the Supreme Court’s most liberal members effectively told us they want no part of this historical destruction. They did so by concurring with their more traditional colleagues in the court’s ruling in American Legion v. American Humanist Ass’n. That case held that a Maryland state agency could constitutionally maintain a Christian cross on public land.

The holding was unexpected. At first glance, the placement of the cross looks like an obvious effort by the state to promote one religion over others. Doing so violates modern interpretations of the First Amendment’s Establishment Clause (“Congress shall make no law respecting an establishment of religion.”)

This cross is huge: 32 feet high. It is highly visible at a busy intersection in Prince George’s County, Maryland. There are no accompanying symbols of any other faiths. Because it is a Latin cross, one might think the state is promoting Western Christianity in particular over its Orthodox or Coptic versions.

But as the court pointed out, in reality the cross is a historical monument. It was erected in 1925 to commemorate soldiers who died in World War I. The monument’s dedication was not primarily a religious event. The sponsors selected the crucial shape because it reminded observers of white crosses in military cemeteries.

Moreover, no one complained about the monument until an anti-religious organization sued to force its removal — 89 years after its dedication.

Even more surprising than the court’s decision is that the justices did not divide 5-4. The vote was 7-2, with Justice Stephen Breyer concurring and Justice Elena Kagan joining his opinion. Breyer and Kagan are among the court’s most liberal justices. And they are both Jewish.

Breyer offered several reasons for his conclusion. He noted the importance of history in clarifying the meaning of the First Amendment. He wrote that “The Latin cross is uniquely associated with the fallen soldiers of World War I” and that the sponsors of the cross, “acted with the undeniably secular motive of commemorating local soldiers.”

He added that a basic purpose of the Establishment Clause was to assure “religious liberty and tolerance for all, avoiding religiously based social conflict.” In his view, ordering the cross’s removal or alteration after so many years would not foster religious liberty or tolerance. Instead it would communicate “a hostility toward religion that has no place in our Establishment Clause traditions.”

We may wonder whether Breyer and Kagan were thinking of the destruction of historical monuments when they joined in this opinion. Regardless, they have reminded us to honor and learn from history rather than try to erase it.

Rob Natelson is a retired constitutional law professor and senior fellow in constitutional jurisprudence at the Independence Institute in Denver. He is the author of The Original Constitution: What It Actually Said and Meant (3rd ed., 2015).