Updated at 2:22 p.m. ET

President Trump stood by his heavily criticized defense of monuments commemorating the Confederacy in a series of tweets Thursday morning. Trump said removing the statues of Confederate generals meant removing "beauty" — that would "never able to be comparably replaced" — from American cities. As he did in a Tuesday press conference, he also attempted to equate some Confederate generals with some of the Founding Fathers.

Strung together, the tweets read:

"Sad to see the history and culture of our great country being ripped apart with the removal of our beautiful statues and monuments. You can't change history, but you can learn from it. Robert E Lee, Stonewall Jackson - who's next, Washington, Jefferson? So foolish! Also the beauty that is being taken out of our cities, towns and parks will be greatly missed and never able to be comparably replaced!" [ellipses removed for clarity]

White House spokeswoman Lindsay Walters declined to discuss the tweets with reporters on Thursday morning, saying, "The tweets speak for themselves."

The online postings come after days of the president whipsawing back and forth on his response to the violence in Charlottesville, Va., that led to the death of 32-year-old Heather Heyer after a man who had attended the white supremacist rally drove his car into a crowd of counterprotesters.

Shortly after that incident, Trump condemned both the white nationalist protesters and the counterprotesters, saying there was an "egregious display of hatred, bigotry and violence on many sides, on many sides."

After Democrats and Republicans alike castigated him for those remarks, the president came out more forcefully against racist groups on Monday, declaring that "racism is evil" and characterizing members of the Ku Klux Klan and neo-Nazis as "criminals and thugs."

But Trump's impromptu remarks at a Tuesday press conference — originally intended to focus on infrastructure — represented a strong swing back to his original position, which suggested equivalency between white supremacist groups and the "alt-right," on the one hand, and the groups who opposed them like Black Lives Matter and leftist anti-fascist protesters, on the other hand.

Leadership from both parties in the House of Representatives also joined the growing debate over Confederate statues.

Minority Leader Nancy Pelosi called Thursday for Confederate statues to be removed from the halls of the Capitol building.

"If Republicans are serious about rejecting white supremacy, I call upon Speaker Ryan to join Democrats to remove the Confederate statues from the Capitol immediately," the California Democrat said, in a statement. "There is no room for celebrating the violent bigotry of the men of the Confederacy in the hallowed halls of the United States Capitol or in places of honor across the country."

The people portrayed in the statues in question are selected by the states. Each state government gets to pick two statues.

House Speaker Paul Ryan, R-Wisc., said the decision to rid the Capitol of Confederate heroes would be a decision "for those states to make," according to a statement from his spokesman provided to Bloomberg.

Sen. Lindsey Graham, R-S.C., who has sometimes been a critic of the president, said in a series of tweets Thursday that Trump needs to act in a manner that doesn't garner praise from racist and hate-filled groups.

"History is watching us all," Graham said, responding to a dig Trump had made at him on Twitter Thursday morning.

Political journalist Ryan Lizza was even more pointed in his reaction, tweeting that Trump had effectively made himself the chief executive of "the Confederate States of America."

Around half of Americans — 52 percent — believe the president's response to the violence in Charlottesville was "not strong enough," according to an NPR/Marist poll released Wednesday. Only 27 percent said it was strong enough (the remainder were unsure).

Those views shift heavily by party — a majority of Republicans, 59 percent, say the president's response was strong enough (compared with 10 percent of Democrats). Meanwhile, an overwhelming majority of Democrats — 79 percent — believe the response was not strong enough (compared with 19 percent of Republicans).

However, more than 60 percent of Americans also believe that statues honoring the Confederacy should "remain as a historical symbol," according to that NPR/Marist poll. And while there is also a partisan divide here, a sizable share of Democrats, 44 percent, believe those statues should remain (along with 86 percent of Republicans and 61 percent of independents).

Debate over removal of Confederate memorials has spread nationwide in recent years, and especially in recent days.

Officials in Lexington, Ky., are bracing for protests as that city moves forward in the process to remove two Confederate statues from its old courthouse. The mayor of Baltimore, Md., had three statues removed hastily, in the dead of night, earlier this week. And in Durham, N.C., a group of demonstrators took matters into their own hands to remove a Confederate memorial.

In Alabama, the state Attorney General's Office has filed a lawsuit against the city of Birmingham and Mayor William Bell for covering a Confederate monument in a park.

While defenders say that such memorials simply represent a part of the nation's history, the monuments and statues are for many Americans a reminder of the nation's painful history of slavery and the people who fought to defend it.

In a widely circulated May speech on his city's removal of four statues commemorating the Confederacy, New Orleans Mayor Mitch Landrieu, a Democrat, explained why he believed that removing the memorials was necessary.

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