As President Trump doubled down on his defense of Confederate statues and monuments this week, he overlooked an important fact noted by historians: The majority of the memorials seem to have been built with the intention not to honor fallen soldiers, but specifically to further ideals of white supremacy.

More than 30 cities either have removed or are removing Confederate monuments, according to a list compiled by The New York Times, and the president said Thursday that in the process, the history and culture of the country was being "ripped apart."

Groups like the Sons of Confederate Veterans defend the monuments, arguing they are an important part of history. One of the leaders of that group, Carl V. Jones, wrote a letter on Aug. 14 condemning the violence and "bigotry" displayed in Charlottesville, but he also denounced "the hatred being leveled against our glorious ancestors by radical leftists who seek to erase our history."

That letter to "compatriots" was signed the day before Trump's raucous press conference, in which he also cast blame on what he called the "alt-left" — comments for which he faced criticism from business leaders, nonprofits and members of his own party, among others.

Yet many historians say the argument about preserving Southern history doesn't hold up when you consider the timing of when the "beautiful" statues, as Trump called them, went up.

"Most of the people who were involved in erecting the monuments were not necessarily erecting a monument to the past," said Jane Dailey, an associate professor of history at the University of Chicago."But were rather, erecting them toward a white supremacist future."

The most recent comprehensive study of Confederate statues and monuments across the country was published by the Southern Poverty Law Center last year. A look at this chart shows huge spikes in construction twice during the 20th century: in the early 1900s, and then again in the 1950s and 60s. Both were times of extreme civil rights tension.

A portion of the Southern Poverty Law Center's graph showing when Confederate monuments and statues were erected across the country. (Southern Poverty Law Center)

In the early 1900s, states were enacting Jim Crow laws to disenfranchise black Americans. In the middle part of the century, the civil rights movement pushed back against that segregation.

James Grossman, the executive director of the American Historical Association, says that the increase in statues and monuments was clearly meant to send a message.

"These statues were meant to create legitimate garb for white supremacy," Grossman said. "Why would you put a statue of Robert E. Lee or Stonewall Jackson in 1948 in Baltimore?"

Grossman was referencing the four statues that came down earlier this week in the city. After the violence in Charlottesville, Va., when a counterprotester was killed while demonstrating, and the action in Durham, N.C., where a crowd pulled down a Confederate statue themselves, the mayor of Baltimore ordered that city to remove its statues in the dead of night.

"They needed to come down," said Mayor Catherine Pugh, according to The Baltimore Sun. "My concern is for the safety and security of our people. We moved as quickly as we could."

Thousands of Marylanders fought in the Civil War, as NPR's Bill Chappell noted, but nearly three times as many fought for the Union as for the Confederacy.

Still, in 1948, the statues went up.

"Who erects a statue of former Confederate generals on the very heels of fighting and winning a war for democracy?" writes Dailey, in a piece for HuffPost, referencing the just-ended World War II. "People who want to send a message to black veterans, the Supreme Court, and the president of the United States, that's who."

Statues and monuments are often seen as long-standing, permanent fixtures, but such memorabilia take effort, planning and politics to get placed, especially on government property. In an interview with NPR, Dailey said it's impossible to separate symbols of the Confederacy from the values of white supremacy. In comparing Robert E. Lee to Presidents George Washington and Thomas Jefferson on Tuesday, President Trump doesn't seem to feel the same.

Dailey pointed to an 1861 speech by Alexander Stephens, who would go on to become vice president of the Confederacy.

"[Our new government's] foundations are laid, its cornerstone rests, upon the great truth that the negro is not equal to the white man," Stevens said, in Savannah, Ga. "That slavery subordination to the superior race is his natural and normal condition."

To build Confederate statues, says Dailey, in public spaces, near government buildings, and especially in front of court houses, was a "power play" meant to intimidate those looking to come to the "seat of justice or the seat of the law."

"I think it's important to understand that one of the meanings of these monuments when they're put up, is to try to settle the meaning of the war" Dailey said. "But also the shape of the future, by saying that elite Southern whites are in control and are going to build monuments to themselves effectively."

"And those monuments will endure and whatever is going around them will not."

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