Pressure to take down America's monuments honoring slain Confederate soldiers and the generals who led them didn't start with Charlottesville. But the deadly violence that rocked the Virginia college town a year ago gave the issue an explosive momentum.

Confederate monuments at public parks, county courthouses and college campuses fell almost daily for weeks after a speeding car killed a woman and injured dozens in Charlottesville on Aug. 12, 2017. The vehicle plowed into a crowd protesting a gathering of white supremacists whose stated goal was to protect a statue of Gen. Robert E. Lee.

At le...