But some Southern blacks are not sure monuments are the best issue to fight over.

Andrew Young, the former Atlanta mayor and civil rights leader, has argued against calls to remove the enormous carved tableau of Confederate leaders on Stone Mountain, Ga., and other Confederate monuments, saying those disputes make more enemies than friends and distract from more substantive issues.

“I personally feel that we made a mistake in fighting over the Confederate flag here in Georgia, or that that was an answer to the problem of the death of nine people to take down the Confederate flag in South Carolina,” he said, referring to the deadly shooting at a landmark black church in Charleston in 2015. He added, “I’m always interested in substance over symbols.”

Others say fighting over symbols is even less fruitful when the symbolism is far murkier, like Christopher Columbus. Democrats have cautioned about a rush to remake civic landscapes, in some ways echoing President Trump but warning that his use of the issue is intentionally divisive. “Making what happened in Charlottesville about monuments is distracting,” Senator Claire McCaskill, Democrat of Missouri, told CNN on Wednesday.

Ms. McCaskill is running for re-election next year in a state Mr. Trump won decisively, and she echoed the Democratic leader, Senator Chuck Schumer of New York, who last week pumped the brakes on calls to rid the United States Capitol of Confederate statues. He said Mr. Trump and Stephen K. Bannon, then the president’s chief strategist, were “trying to divert attention” from the president’s refusal to offer a full-throated denunciation of neo-Nazis and other white supremacists whose rally in Charlottesville led to the death of a counterprotester.

Supporters of white nationalist groups maintain that a fervor to tear down monuments only builds their ranks. “It’s a tragedy these monuments are coming down, but every time antifa overreacts, it’s making friends for Confederate heritage,” said Kirk D. Lyons, a North Carolina lawyer, who has been professionally and socially tied to some of the nation’s most visible hate groups. (He denies that he is a white supremacist and describes himself as “a Christian attorney of Southern ancestry.”) Antifa is shorthand for anti-fascist activists.

In polls taken since Charlottesville, majorities of Americans favor keeping Confederate monuments intact, although there are sharp splits by race and party affiliation. Pluralities of Democrats and blacks favor removal, while whites and Republicans oppose altering the status quo. Support for changing street names and other less tangible symbols falls off sharply. That has not stopped Democrats in the Maryland General Assembly from trying to change lyrics to the state song, “Maryland, My Maryland,” a mid-19th-century ditty that calls on Maryland to join the Confederacy.

Larry Sabato, a political scientist at the University of Virginia who watched neo-Nazis march on his own campus, said the left seems to have once again become focused on symbolic issues rather than the ones that most voters care about.