It’s a dangerous time to be a statue in America. The renewed push to take down Confederate monuments amid national soul-searching on race has turned into a more general war on problematic monuments. Several New York City Council members want Thomas Jefferson’s statue removed from the council’s chambers because of his slave ownership. In other cities, protesters have toppled and defaced statues of Christopher Columbus, George Washington, and Ulysses S. Grant, the man who defeated the Confederacy.

Is this surge in iconoclasm a healthy reevaluation of heroes and images we look up to, or a barbaric assault on our historic and cultural legacy?

The answer varies from case to case. There is nothing wrong with removing monuments when there is a consensus that they offend our moral sense — though in a democracy this should be done by legal process, not mob action.

The easiest decision is monuments honoring Confederate leaders who rebelled against the United States to preserve slavery. Most of these monuments were erected in the 20th century, as symbols of legalized white supremacy in the South. In a sense, they are not that different from monuments to Communist leaders in Eastern Europe: idols glorifying a failed regime built on human subjugation.

One can also justify the planned removal of the Theodore Roosevelt statue from the front steps of New York City’s American Museum of Natural History. The move has been decried as Roosevelt’s “cancellation.” But the actual issue is the design that depicts the late president on horseback towering over an African and a Native American, and the museum is simultaneously renaming a wing after him.

But most of the attacks on the monuments are at best misguided and at worst obscene.

Is it deplorable that Washington and Jefferson owned other humans — like many people of their class — despite professing to abhor the practice? Yes, of course. Jefferson’s complicated history includes active anti-slavery advocacy in the first half of his career, later compromise and silence, and presiding over a large household that ran on slave labor.

Yet, while slavery is a stain on this country’s birth, the principles of liberty and equality championed by the founders were instrumental in advancing human freedom and well-being — including, eventually, abolition of slavery. To honor them is to recognize that achievement, not to deny these men’s public and private flaws. To revoke those honors would be a symbolic statement that the American republic itself is “canceled,” like the Confederacy or the Soviet Union.

Going after Grant, a man who consistently (if not always effectively) championed the civil rights of African-Americans, is absurd. True, at one point Grant reluctantly owned — but soon freed — a slave given to him by his wife’s family. But how many public figures from the past completely escape the moral pitfalls of their time? Particularly unconscionable was the attack in Madison, Wisconsin, on the nearly century-old sculpture of Col. Hans Christian Heg, an abolitionist who died fighting in the Civil War. The statue was toppled, decapitated and thrown into a lake by rioters. This is not activism; it’s nihilistic destruction.

The mob attacks on American’s monuments must stop — or be stopped. They are wrong. They are also giving President Donald Trump culture-war ammunition.

But this is also an opportunity for Joe Biden. He needs to unequivocally condemn the vandalism and lawlessness while recognizing legitimate concerns about some monuments. A strong statement on the issue would show leadership — and show that the Democratic Party still belongs to moderates and liberals, not extremists.