Representative Barbara Lee was in a hurry. The House was preparing to advance a multitrillion-dollar budget blueprint and voting rights bill during a rare August session, ending a standoff with a gang of conservative Democrats threatening to derail President Joe Biden’s domestic agenda. A frantic two-day session on Capitol Hill was coming to a close, and the California congresswoman had to go vote.

Since Biden’s withdrawal from Afghanistan and the collapse of the US-backed Afghan government, Lee has had a lot on her mind. Just three days after 9/11, as the ruins still smoldered and the country reeled in shock, Lee cast the loneliest vote in her political career. She was the sole member of Congress—House and Senate—to vote against a resolution to give President George W. Bush sweeping authorization to use military force in Afghanistan.

I wanted to speak with Lee about her historic vote and the lessons to learn from America’s longest-running war. But she was behind schedule, juggling phone calls between votes and remarks. She tried to fit as much into my interview with her as quickly as she could, knowing she’d have to get back on the House floor at any moment. I wasn’t the only journalist trying to get her on the record—as the Biden administration winds down America’s military adventure in Afghanistan, everyone wants to hear from the one lawmaker who got it right.

“I urged caution because I knew even then that there was no military solution in Afghanistan,” she said. As far as she was concerned, the 60-word resolution amounted to “a blank check for any president to use force anywhere in the world.”

For the last two decades, presidents from both parties have relied on the 2001 resolution to wage war around the globe. It has served as the legal justification for everything from Guantánamo Bay, the illegal torture camp the US operates on Cuban soil, to Biden’s recent air strikes in Somalia. Lee has reintroduced legislation to repeal the authorization every year since.

“I don’t think the public wants to see their tax dollars going into nation-building,” she said. “I think they do want to see their tax dollars going for diplomacy, development, humanitarian concerns, trade, aid, and really engaging in the world for global peace and security in a way that prevents the necessity to use force or prevents much of what causes terrorism. Because we know that the seeds of terrorism are sown, in many respects, in despair.”

Lee’s explanation for her vote that day in 2001 was sweeping, nearly free-associative, ranging from her college education to the circumstances of her own birth. (Her mother was made to wait for hours in a segregated hospital before getting a C-section, a delay which nearly killed them both.) “It was based on my understanding of the Constitution,“ she said. “It was based on my faith—it was a moral decision because I knew that many were going to get killed.”

Studying psychology, and going on to specialize in psychiatric social work, Lee added, taught her that giving into aggressive impulses on September 14 may not have been the wisest choice. “You don’t make critical decisions when you’re grieving, angry, anxious, and, in many ways, not certain what the appropriate response is.”

There was also a sense of duty, that Congress shouldn’t abdicate its constitutional responsibilities to debate and vote on matters of war. Giving the president unilateral war powers, Lee said, “gave away my constituents’ voice.”

“So there are many things that came together and convinced me intellectually and emotionally that that was the right vote,” Lee said. “And I still believe that was the right vote. Anyway, I have to go vote.”

In late 2001, Lee received so many death threats that Capitol Police forced her to get around-the-clock security protection. Thousands of letters and phone calls flooded her office. Those who stopped short of calling her a traitor swore that she would lose reelection. Her constituents, on the other hand, voted her back into office for 10 more terms.

Though recent events have, to many, vindicated her historical role, Lee isn’t dwelling on the past. Today, she’s focused on achieving the evacuation of “all American citizens, Afghan allies, children, women, everyone who needs to get out of there due to the risk of being killed.” Lee, along with other lawmakers and congressional staff, has been scrambling to help people get out of Afghanistan quickly, doing casework for special immigrant visas. As chair of the Appropriations Subcommittee on State and Foreign Operations, she’s also using her influence to fund humanitarian assistance. The afternoon we spoke, the John Lewis Voting Rights Advancement Act was going before the House.

“I do have to run,” she said. “I’m voting for somebody else too, proxy. I’m sorry, Aida, but this is just one of those days.”