As a mob of President Donald Trump’s supporters, seemingly undeterred by Capitol Police, breached the Capitol doors and stormed the floors of the House and Senate on Wednesday, National Guard troops, deployed to quell protests outside the White House last summer, were noticeably absent.

At 3:36 p.m. Eastern time, nearly two hours after the first protesters had swarmed past security and into the Capitol, White House Press Secretary Kayleigh McEnany tweeted that the National Guard had been ordered to respond to the uprising.

The White House announcement came minutes after Virginia’s Democratic governor, Ralph Northam, announced that he was sending members of the Virginia National Guard and Virginia State Troopers to help restore order.

Why the delay in deploying the D.C. Guard? The traditional chain of command for the District of Columbia’s National Guard does not exist. In states, the governor is the commander of that state’s National Guard units and can unilaterally deploy them under his or her own authority.

But as the nation’s capital has no governor, the chain of command goes up through the Army secretary to the president.

“The D.C. Guard has been mobilized to provide support to federal law enforcement in the District,” Pentagon spokesman Jonathan Hoffman said in a statement. “Acting Secretary Miller has been in contact with Congressional leadership, and Secretary McCarthy has been working with the D.C. government. The law enforcement response will be led by the Department of Justice.”

Ryan McCarthy, the Army secretary, ultimately deployed the entire D.C. National Guard, approximately 1,100 personnel, to quell the mob.

“Every governor has control of the Guard, and the District is different,” D.C. Mayor Muriel Bowser told reporters late Wednesday. “Over many months, the secretary of the Army and I know how to communicate to have requests approved as quickly as possible.”

Chris Miller, who stepped in as acting Defense secretary after Trump fired Mark T. Esper in November, put out his own statement, saying the department is “prepared to provide additional support as necessary and appropriate as requested by local authorities. Our people are sworn to defend the constitution and our democratic form of government and they will act accordingly.”

Miller did not mention Trump in his statement, prompting speculation that Vice President Mike Pence actually got the ball rolling on deploying the D.C. Guard to the Capitol.

The D.C. National Guard was widely deployed across Washington during protests in June 2020. Guard members from D.C. participated in clearing protesters from Lafayette Square, directly across from the White House, when Trump and others — including Esper, the Defense secretary at the time, and Gen. Mark Milley, the chairman of the Joint Chiefs — walked across the park for a photo op in front of St. John’s Church.

After significant criticism of those events, as well as calls for the military to stay out of the transition of power between administrations, defense officials may have been hesitant to involve uniformed members of the military.

The National Guard Bureau’s initial response to queries about why it had not deployed units to the Capitol was that no request for troops had been made.

Later, Rep. Elissa Slotkin, D-Mich., tweeted that she had been in touch with Milley and that National Guard troops had been approved. House Armed Services Chairman Adam Smith, D-Wash., had gotten the same information from McCarthy, she said.

“This attempted coup and domestic terrorist attack needs to end immediately,” Smith tweeted just before 4 p.m.