President Trump’s threat Friday to involve the military more deeply in the response to looting in Minneapolis pulled the military into a political fray over the issue, but he is unlikely to follow through despite his authority to deploy armed forces, defense officials and national security experts said.

The threat came in a pair of tweets from the White House during protests that escalated into violence following the death of a handcuffed black man, George Floyd, who was pinned down by the neck with an officer’s knee. Trump tweeted as scenes of a police station and other buildings burning in Minneapolis aired on television amid calls for the officer’s arrest.

“These THUGS are dishonoring the memory of George Floyd, and I won’t let that happen,” Trump tweeted, using a term with racist connotations for those involved in the looting. “Just spoke to Governor Tim Walz and told him that the Military is with him all the way. Any difficulty and we will assume control but, when the looting starts, the shooting starts. Thank you!”

In another tweet, Trump said he “can’t stand back & watch this happen to a great American City, Minneapolis,” and blamed local officials there for a “total lack of leadership.”

Trump’s reaction immediately pulled the Pentagon into a crisis that already has racial and political dynamics. It follows other incidents in which the president has politicized the military, including the deployment of active-duty service members to the southern border, threats to North Korean leader Kim Jong Un on Twitter and intervention into criminal justice cases.

Troops historically have been put under federal control to quell unrest only when more local forces were unable to do so, said Lindsay Cohn, a professor at the Naval War College. While federalized troops can be effective peacekeepers in situations where trust between police or civilians is broken, she said, Trump’s comments indicated he wanted to use military force in a suppression role, and are consistent with his tendency to use tough-guy rhetoric.

“His base also tend to have very high confidence in the military and to see them as effective, so this appears to be politicized use of the idea of the military to appeal to the president’s political supporters,” she said.

The Pentagon historically dislikes overseeing troops under federal control to handle unrest, preferring to leave them to the National Guard under state orders. Under federal orders, Cohn noted, the Defense Department picks up the majority of the cost, rather than the state.

Trump’s tweets had parallels to his comments about the southern border in 2018, when he suggested that if migrants threw rocks at U.S. troops dispatched there, American forces should act as if the rocks are rifles. After a backlash, Trump said the migrants would not be shot.

Walz, a Democrat and retired command sergeant major in the National Guard, already had activated guard members to assist police on Thursday, a point that Trump did not acknowledge. The governor’s decision follows similar actions by other governors amid unrest prompted by the death of black men at the hands of police, including in Ferguson, Mo., in 2014, and in Baltimore in 2015.

In those cases, the guard members operated under state orders and did not have a leading role, as government officials sought to de-escalate tensions. Under such orders, guard members can take on law enforcement duties, but frequently do not. In Minnesota, they will not have authority to arrest and will be armed for their own self-defense, state officials said.

Trump also has the authority to order federalized troops to Minnesota under laws such as the Insurrection Act, which allows presidents to deploy the military domestically during emergencies without a governor’s permission, said Stephen Vladeck, a professor at the University of Texas School of Law.

Such actions are rare but have occurred, most recently in 1992 amid rioting in Los Angeles after the police beating of Rodney King was recorded on video. At the time, President George H.W. Bush deployed 4,000 active-duty soldiers and Marines to complement thousands of National Guard troops and police.

“This is one of those areas where I think the law is actually a lot scarier than we might like it to be,” Vladeck said. “It’s the practical and political constraints that are the political checks” on power.

Vladeck added that if the president deploys forces under federal orders, he would be responsible for whatever happens.

“Right now, if things go well he can say that he told Walz to do it, and if things go badly, he can say, ‘It’s all Walz’s fault,’ ” Vladeck said.

A senior defense official, speaking on the condition of anonymity to discuss internal deliberations, said Defense Secretary Mark T. Esper and the chairman of the Joint Chiefs of Staff, Gen. Mark A. Milley, had spoken with Walz on Friday. The two officials “pledged to support him in any way that he would need,” the official said. “The governor had no requests at this time and the Defense Department is not sending any additional assets.”

Gen. Joseph Lengyel, the chief of the National Guard Bureau, spoke with the president on Friday about the unrest, a defense official said. He declined to discuss internal deliberations.

The Minnesota National Guard said Friday that Walz had activated about 500 guard members, including some who were on duty Thursday night.

Peter Feaver, a scholar on civil-military relations at Duke University, said Trump’s warning on Twitter was likely to result in a planning process among government officials but didn’t constitute a presidential order.

Feaver noted that Bush employed active-duty troops to assist in Louisiana when local authorities were overwhelmed by the scale of the destruction following Hurricane Katrina in 2005. But state authorities rejected White House requests to put the National Guard there under federal control. The situation in Minnesota, Feaver said, does not appear to have reached the same scale of crisis that followed Katrina.

“It does feel a little more politically opportunistic for the president to insert himself in this,” especially when the governor is not requesting it, Feaver said.

“The use of the military by federal authorities in domestic situations, while it’s precedented, it also tends to be very controversial,” he said. “It’s a politically fraught move.”

By Friday afternoon, Trump appeared to backtrack on his late-night tweets.

In a follow-up message, he recast his comment about looting leading to shooting by noting that a man had been shot to death in Minneapolis on Wednesday night, and that others had been shot in Louisville on Thursday.

“I don’t want this to happen, and that’s what the expression put out last night means,” he tweeted. “It was spoken as a fact, not as a statement. It’s very simple, nobody should have any problem with this other than the haters, and those looking to cause trouble on social media. Honor the memory of George Floyd!”