In the days after the 9/11 attacks in 2001, just one member of Congress voted against giving President Bush authority to go to war in Afghanistan.

       Barbara Lee, a Democratic representative from California, warned at the time that approving the so-called Authorisation for the Use of Military Force (AUMF) could mean the US would be embarking “on an open-ended war with neither an exit strategy nor a focused target.”

       Now, 20 years later, the 2001 AUMF remains in effect, having been used to justify incursions in at least 21 different countries, and Ms Lee’s passionate speech from the time defending her controversial vote has gone viral, as Afghanistan returns to the headlines.

       On 14 September, the congresswoman, who represents a district in the San Francisco Bay Area, gave a speech on the House floor, knowing full well that none of her colleagues was joining her in opposing the AUMF, which she argued would give the president carte blanche.

       “Our country is in a state of mourning. Some of us must say, let’s step back for a moment. Let’s just pause, just for a minute, and think through the implications of our actions today, so that this does not spiral out of control,” she said.

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       “Now, I have agonised over this vote. But I came to grips with it today, and I came to grips with opposing this resolution during the very painful, yet very beautiful, memorial service. As a member of the clergy so eloquently said, as we act, let us not become the evil that we deplore.”

       Eventually, the other 420 members of Congress passed the authorisation anyway, giving the president authority to use “all necessary and appropriate force” to attack “nations, organisations, or persons” responsible for 9/11, or anyone who “harboured” these groups, “in order to prevent any future acts of international terrorism against the United States.”

       This broad definition was used to justify the war in Afghanistan, as well as lesser-known US deployments to Chad, Niger, Eritrea, and the Philippines. All told, the order has been the legal framework for at least missions in at least 21 countries around the world, stretching well past the original groups and nations most tied to 9/11.

       The 2001 AUMF, as well as a subsequent one authorising the war in Iraq in 2002, remain in effect, though Congress is heading towards repealing the latter, and legislation was introduced last week in the Senate to repeal the former.

       An AUMF hasn’t been repealed successfully in the last 50 years, and critics say Congress has yielded too much of its authority to decide when the country goes to war to the president.

       As many of Ms Lee’s predictions continue coming true in Afghanistan, the California rep called on leaders to eschew further military intervention and focus on what she called the “humanitarian crisis” underway in the country as the Taliban takes over and the US withdraws most of its troops.

       “What’s happening in Afghanistan currently is a humanitarian crisis,” she said on Sunday on Twitter. “Let’s be clear: there has never been, and will never be, a US military solution in Afghanistan. Our top priority must be providing humanitarian aid & resettlement to Afghan refugees, women, and children.”

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