A former chairman of the Joint Chiefs of Staff says he was “sickened” to see National Guard troops and other security personnel forcibly clear protesters from a square near the White House to facilitate President Donald Trump’s walk to a nearby church to pose for photographs.

Calling the visit Monday a “stunt,” Mike Mullen, a retired Navy admiral who headed the military from 2007 to 2011, wrote in The Atlantic on Tuesday it laid bare what he called Trump’s “disdain” for the rights of peaceful protesters. He said it also risked further politicizing the military.

Mullen cautioned against an overly aggressive use of the military to restrain the sometimes-violent protests around the country. He said he has confidence in the professionalism of the troops but worries about the soundness of the orders they would be given by Trump.

“All Americans were rightly sickened and revolted by the brutal death of George Floyd,” Trump said in his Monday speech, announcing his administration’s work to defuse riots. “My administration is fully committed that, for George and his family, justice will be served. He will not have died in vain, but we cannot allow the righteous cries and peaceful protesters to be drown out by an angry mob.

“The biggest victims of the rioting are peace-loving citizens in our poorest communities and as their president, I will fight to keep them safe. I will fight to protect you. I am your president of law and order and an ally of all peaceful protesters.

“But in recent days, our nation has been gripped by professional anarchists, violent mobs, arsonists, looters, criminals, rioters, Antifa, and others.”

Thousands of protesters gathered across the street from Lafayette Park near the White House on Tuesday, as military and civilian law enforcement personnel stood on the other side of a black chain link fence that had been put up overnight to block access to the park.

The crowd chanted the name of George Floyd and Black Lives Matter. Floyd is the black man who died while in police custody in Minnesota.

The protesters stood in front of the historic church where President Donald Trump went for a photo op Monday night after the area around Lafayette Park was cleared of protesters by law enforcement officials using smoke canisters and pepper balls.

When Washington’s 7 p.m. curfew hit, the protesters did not budge. Instead, they used an expletive to describe what they thought of the curfew and defied warnings from federal officials that the response from law enforcement could be even more forceful.

Attorney General William Barr ordered law enforcement officials to clear Lafayette Park and push back the perimeter around the White House when he arrived there Monday evening, leading to police using tear gas to disperse protesters.

A person familiar with the matter tells The Associated Press that Barr expected the perimeter to have been extended much earlier Monday.

The person said officials had met that morning and decided the perimeter had to be moved by at least one full block after multiple fires were set in the park the night before. They said that was expected to happen by Monday afternoon.

The person said Barr was surprised it had not been done when he arrived in the early evening and directed action to be taken. They said he assumed police would use “typical crowd control measures” against protesters who resisted commands to clear the area.