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When rioters egged on by President Trump stormed the Capitol a week ago, Sen. Tammy Duckworth wasn’t in the Senate chamber with her colleagues. She was in the complex’s underground tunnels, en route to the Senate floor, where she planned to speak in favor of certifying the Electoral College ballots in the 2020 U.S. presidential election.

But that speech was not to be. Before Duckworth could board the train to the floor, Capitol Police told her that rioters were pressing against the building doors and requested that she find a secure location to shelter in place. With the building on lockdown, the Illinois senator faced further safety considerations compared with some of her colleagues; as a wheelchair user, it’s not as simple for her to evacuate.

Duckworth’s military training kicked in, and she remained calm while also keeping in touch with her colleague, Sen. Amy Klobuchar, to learn what was happening outside her lockdown location.

“As a soldier, I’ve been to places where I help other people fight for democracy,” Duckworth says. “And yet here I was, and I couldn’t do anything about it in the moment.”

In an interview with Fortune, Duckworth reflected on what was going through her mind on Jan. 6—and what needs to happen next. This interview has been edited and condensed.

Fortune: Where were you during the attack on the Capitol? What was going through your mind?

Sen. Tammy Duckworth: I was on my way to the floor—I was in the tunnels. I was supposed to speak at 2:50 p.m., and they breached the Capitol right around that same time. In the tunnels to catch the train, the Capitol Police said I could continue forward if I wanted to, but they would prefer if I would take myself to a secure location. Instead of continuing on to the floor, I went to a secure place with my staff members.

I was pretty calm. I was talking with Senator Klobuchar; I couldn’t believe the Capitol had been breached, that the Capitol Police could be overwhelmed. It was unbelievable to me that folks who call themselves patriots would actually be trying to overthrow the government and stop us from doing our constitutional duty to certify the ballots.

I was just waiting, making sure leadership knew I was fine—not to worry about me. I always carry provisions in my backpack—water, aspirin, Tylenol, power bars. I was okay to hunker down for a little bit.

Lawmakers with military backgrounds seemed to remain calm throughout the situation. Did that training and experience kick in for you?

Definitely. I knew exactly what the Capitol Police were facing and what needed to be done. I knew the best thing we could do was to stay out of their way—to be one less factor for them to worry about.

I always know where the back way out of a room is. I always say, old habits die hard. And I knew that I could take care of myself.

Once I knew that the ballots had been secured—that was one of the worries I had.

Were you worried about the accessibility of the Capitol complex as someone who uses a wheelchair?

Yes, that’s why I did not continue on to the floor. I was given the option, but I knew that if the Capitol was breached there’s only one way in and out for me. There are multiple doors into the floor of the Senate chambers, but I can only really go in and out of the doors behind the dais. I can only use the elevators. I knew that putting myself in that situation was going to make things more difficult for everyone all around if they had to evacuate us, so that’s why I chose instead to shelter in place.

The public has recently learned more about some of the dangers—like Rep. Ayanna Pressley’s panic buttons being ripped out. Has anything else come to light for you?

They did not make it to my main offices, although they did attempt to gain entry to my hideaway [private offices located near the Senate floor], because it has a window to the outside. That window was shattered. Thank goodness it held so that they never breached my hideaway. Had I been in there I would have been in real jeopardy. It’s pretty badly cracked, and the inside of my hideaway is filled with shattered glass.

What does it feel like for you to see that damage?

For me, it’s frustration. Because I couldn’t do anything about it. As a soldier, I’ve been to places where I help other people fight for democracy. And yet here I was, and I couldn’t do anything about it in the moment. And so it was really frustrating to me to see people carrying the American flag—the same flag I wore on my uniform when I went into combat—but they were carrying the flag to attack our Capitol and to try to basically overthrow the Constitution. And that imagery was far more hurtful than broken glass in my hideaway. Glass can be replaced, furniture can be fixed.

There was a determined group within that crowd that that were systematic in how they reached the Capitol and were well coordinated.

What needs to happen next?

We need to track down everyone who was involved, and there need to be consequences for those actions. And then we need to review the security plans. The Capitol Police worked very, very hard. And they reacted the best they could, but they were overwhelmed and basically let down by their leadership. We need to look at the leadership of the Capitol Police, and then we need to look at the agreements—the fact that [D.C. Mayor Muriel Bowser] did not have the ability to call up the D.C. National Guard, for example.

And as for President Trump?

We’re about to go to impeachment. I think he needs to face the consequences for his actions as well. He needs to be barred from ever holding office again.

Sen. Tammy Duckworth’s experiences as a soldier and wheelchair user shaped her response to the Capitol riots

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