Many people who do not identify as white supremacists support keeping the monuments as a connection to their history and heritage.
A NPR/PBS NewsHour/Marist poll on Monday and Tuesday of 1,125 adults showed 86 percent of the Republicans surveyed thought Confederate statues should remain in place as a symbol of history.
Mr. Trump’s tweets came the morning after his personal lawyer forwarded an email to conservative journalists, government officials and friends that painted Lee in glowing terms and echoed secessionist sentiment from the Civil War era.
On Saturday, the day of the protests, Mr. Trump did not condemn neo-Nazis or white supremacists in his public remarks about the violence, prompting criticism that his omission suggested support for the racist groups. An Ohio man with white supremacist ties is accused of driving his car into a crowd, killing one woman and injuring 19 people.
Two days later, Mr. Trump bowed to pressure and said racism was “evil” and named racist organizations in his follow-up remarks about Charlottesville. But on Tuesday, Mr. Trump reverted to his initial public posture and blamed “both sides” for the violence.
Mr. Trump said many of those who opposed the statue’s removal were good people protesting the loss of their culture, and he questioned whether taking down statues of Lee could lead to monuments of George Washington also being removed.
Some in favor of keeping the statues argue that the interpretation of the monuments could be revised to teach future generations about white privilege. But practically, that is unrealistic, said W. Fitzhugh Brundage, a history professor at the University of North Carolina. Mr. Brundage said it would be expensive to add explanatory plaques next to the Confederate monuments, and that may not be a prominent enough display of the reinterpretation.
To those who argue that the statues are not about hate but heritage, Mr. Brundage said relocating them to a museum would not erase the heritage.
“You’re not erasing history,” Mr. Brundage said. “You’re just transforming a landscape so that you can make it one you’re comfortable living in.”
Corey Stewart, a Republican who has said he plans to run against Senator Tim Kaine, Democrat of Virginia, in 2018, defended Mr. Trump on Thursday.
“The president is absolutely right,” Mr. Stewart, who was Mr. Trump’s campaign chairman in Virginia, said on CNN. “After they get done removing statues to Confederate generals because, arguably, they fought to preserve the institution of slavery, they are going right after slave owners, including the founders — Jefferson, Madison, Washington — and when you undermine the founding fathers, you undermine the founding documents, namely the Constitution of the United States.”