The U.S. military, under scrutiny for its role in efforts to quell protests and its own difficult history involving race, is facing another reckoning as it weighs how to confront a legacy of Confederate symbolism without running afoul of President Trump.

Momentum toward possible changes had been building in the Pentagon, with the Marine Corps releasing a policy last week prohibiting the display of the Confederate battle flag at its installations. The other services also acknowledged that they were discussing the issue, which the military has avoided for years.

But Trump’s intervention in one of the most significant parts of the discussion — whether to change the names of the 10 Army bases named after Confederate officers who fought to preserve slavery — has left military officials unclear on how to proceed, according to six defense officials familiar with the issue. Again, some of them said, the president has dragged an institution that prides itself on remaining apolitical into a heated partisan and cultural fight.

“I think we kind of have whiplash right now,” said one defense official, who like several others spoke on the condition of anonymity because of the sensitivity of the issue. “We don’t know what’s next.”

The conversation in the Army that drew the president’s wrath had included the possibility of forming a blue-ribbon committee comprising retired service members, historians and lawmakers from both parties, including people of color, to develop recommendations for renaming the bases and other measures, according to three defense officials. The service had declined to do so for years, including during the Obama administration.

Senior Pentagon officials still want to proceed with other aspects of the plan, including prohibitions on displaying the Confederate battle flag, two senior defense officials said. But “everyone is aware of the president’s position” on renaming bases, and they are proceeding cautiously on the related issues because of it, one of those officials said.

Trump’s rebuke in tweets Wednesday came after several days of mounting frustration and minutes before White House press secretary Kayleigh McEnany went to brief reporters. She expected to be asked about the issue and sought direction from the president, said three people familiar with the decision.

Trump became animated as he talked about it with staffers, aides said. He had not been told that Pentagon officials would disclose on Monday that Defense Secretary Mark T. Esper and Army Secretary Ryan McCarthy were open to bipartisan discussion about renaming bases. The president felt that he had to stop any changes, the officials said, asking, “Where will it end?”

The Senate Armed Services Committee, led by Republicans, also had just approved an amendment proposed by Sen. Elizabeth Warren (D-Mass.) in the defense spending bill that would require the Defense Department to rename bases, buildings, streets, weapons and other “assets” that are named after Confederate leaders.

After a wide-ranging discussion, the staff decided that the president would announce his position in tweets and that McEnany would speak on the matter at the briefing, the officials familiar with the discussion said. Nearly immediately, Trump tweeted that his administration “will not even consider” renaming “legendary” bases such as North Carolina’s Fort Bragg, Georgia’s Fort Benning and Fort Hood in Texas, all of which are named after Confederates.

“Our history as the Greatest Nation in the World will not be tampered with,” Trump tweeted. “Respect our Military!”

Trump has long been opposed to such efforts, including the proposed removal of a statue of Confederate Gen. Robert E. Lee at the center of white-nationalist protests in Charlottesville in 2017 that turned violent. He sees such efforts as “politically correct” actions that offend his supporters who are proud of their heritage, the officials said. He had watched on television this week as protesters tore down statues of Confederate leaders in several cities.

“Don’t they have more important things to be doing?” Trump told senior staff members this week of the military officials discussing changes to base names, according to one person with direct knowledge of his comments.

The Navy’s top officer, Adm. Michael Gilday, also had just announced Tuesday that he was planning prohibitions on Confederate battle flags, similar to the Marine Corps’.

The Air Force, whose leaders have spoken passionately about racism since the killing of George Floyd in Minneapolis police custody last month, planned to release a policy Thursday that prohibited the display of the Confederate battle flag, amid a broader discussion about injustices, three defense officials said. But they have held back after the president's rebuke of the Army.

The Coast Guard, which is part of the Department of Homeland Security, also has not yet addressed the issue publicly.

The episode comes amid an extraordinary period of tension between Trump and the military, including opposition from Esper and Gen. Mark A. Milley, the chairman of the Joint Chiefs of Staff, over Trump’s desire to use active-duty troops to respond to protests prompted by Floyd’s death. Trump ultimately acquiesced but only after shouting at the two leaders, senior administration officials said.

Trump also has been frustrated by criticism of Esper and Milley’s presence with him on June 1 as he walked from the White House to a nearby church that had been partially burned during demonstrations. Trump is more frustrated with Esper than Milley, two officials said, and generally has more positive feelings toward Milley.

Peaceful protesters had just been forcibly cleared from the area, prompting former defense secretary Jim Mattis and other past military officials to decry the appearance of senior Pentagon officials supporting a crackdown on freedom of speech. Milley and Esper have since apologized.

The Army bases named after Confederate soldiers were mostly established in the 20th century as the United States was training for World War I and needed vast open space. They courted approval from officials in Georgia, North Carolina and other Southern states and in some cases gave camps names requested by local officials.

Proposals to ban Confederate names could include buildings, ships and street names on bases in the other services, too.

The Navy, for example, has a warship that was named the USS Chancellorsville in 1989, after a Confederate win in the Civil War. While other ships in its class also are named after famous battles, including American losses, the ship's coat of arms includes an inverted wreath to recognize the death of Confederate Lt. Gen. Thomas “Stonewall” Jackson, according to a Navy history of the ship.

Buildings at military installations also have been named after Confederates, including Lee Barracks at the U.S. Military Academy at West Point, N.Y.

Eliminating the symbolism, including the Army’s base names, would be a first step that shows the military is serious about more-substantive change, said Terron Sims II, a former Army captain and Iraq War veteran.

Sims, who is black, said that when he returned from the war, he was assigned to Louisiana’s Fort Polk, which is named after a Confederate general.

“I can’t speak for how white people have felt for all these years,” said Sims, a graduate of West Point now active in Democratic politics. “But as a black person, you find it odd having to serve on an installation that is dedicated to someone whose sole purpose in life was to keep you in bondage.”

John Estrada, a retired Marine Corps sergeant major, said he was proud to see Gen. David Berger, the commandant of his service, announce in April that he was banning the display of Confederate battle flags and then follow through with a new policy.

Berger said that while some see the flag as a symbol of their heritage, it “carries the power to inflame feelings of division” and can weaken unit cohesion needed in combat.

Estrada, a black immigrant who became a U.S. citizen while serving in the military, said that when he sees a Confederate battle flag flying on a vehicle near him on a back road, it still evokes anger and fear in him. He is in favor of banning the display of flags on bases and changing the names of Army bases.

“I’m not saying that everyone who adores the Confederate flag is racist, by any means,” said Estrada, who served as the U.S. ambassador to his native Trinidad and Tobago during the Obama administration. “But it’s what that symbol represents to people of color — black people, especially. It represents bondage. It represents people who embrace that.”

Activists should not let up on addressing the issue of Confederate flags and names in the military, said Richard Brookshire, a former Army sergeant who now takes part in Black Lives Matter demonstrations.

Brookshire, who deployed to Afghanistan as a medic, said that while assigned to a U.S. unit in Germany he saw a fascination with Nazism among fellow soldiers that concerned him. After leaving the military, he co-founded the Black Veterans Project, a nonprofit organization that advocates for black veterans.

“The time is now and the time has always been now to remove the vestiges of slavery from American institutions,” Brookshire said of eliminating Confederate symbolism in the military. “I don’t want to say it’s the easy way out. But it’s the easiest way to remove a symbol of white supremacy.”