On Wednesday, after chemical irritants were fired in the Capitol to repel a pro-Trump mob, Rep. Ruben Gallego thought of the moment years ago when he entered a Marine Corps gas chamber.

The training was suddenly relevant for the Iraq veteran and Arizona Democrat after an announcement blared to don gas masks stored under the seats. Gallego looked over the panicked faces of fellow lawmakers and explained to them some of the most potent lessons from boot camp. Trust your mask. Take measured, shallow breaths. Don’t panic.

Police barricaded doors and pointed pistols at infiltrators through broken windows. Gallego removed his jacket. “I thought I’d have to fight my way out,” he told The Washington Post in an interview.

Gallego was among a handful of veterans-turned-lawmakers who reverted to military training after a mob smashed windows, broke down doors and rushed past federal police in an attack. One woman was shot and killed by police inside the Capitol.

Rep. Jason Crow (D-Colo.), a former Army Ranger who served in Iraq and Afghanistan, also soothed colleagues on the balcony and compared the moment to flashes of combat. He told them to remove pins identifying them as lawmakers and wielded his sole weapon — a pen, he told CNN.

“I haven’t felt that way in over 15 years since I was a Ranger in Iraq and Afghanistan,” Crow said.

Gallego said that with the House floor in chaos and police focused on sealing the doors, few were left to take charge.

So Gallego, whose mind flipped to a “Marine Corps brain,” became Cpl. Gallego. He stood on a chair and barked instructions to move toward exits. Crow made similar efforts up in the balcony, he said, and photos show him comforting Rep. Susan Wild (D-Pa.).

Colleagues, some elderly and frightened, needed help with their masks. Gallego didn’t don his, he said, but he helped others by relaying long-dormant tips, such as breathe slowly to avoid hyperventilating. He took in surreal moments, like a chaplain offering to pray in a time of action.

About 15 minutes passed before lawmakers and staff were ushered off the floor and into secure locations. Gallego said he and Rep. Eric Swalwell (D-Calif.) were the last ones to leave after ensuring that everyone else had been evacuated.

Gallego was still amped up from the event hours later.

“I have that combat adrenaline rush going through me right now,” he said as midnight neared Wednesday.

But Gallego and Crow were not the only veterans in the Capitol that day.

Ashli Babbitt, who served in Iraq with the Air Force, was shown in videos trying to climb through a broken window inside. She was shot and later died of her wounds, police said.

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