Less than a month after the 9/11 attacks, American and allied forces began combat operations in Afghanistan, targeting al Qaeda and the Taliban regime that had been giving al Qaeda protection.
Nearly two decades later, the United States withdrew most of its troops from Afghanistan and the Taliban regained control of the country's capital.
US President Joe Biden admitted that the collapse of the Afghan government happened more quickly than his administration had anticipated, but he refused to back away from his decision to end America's longest war.
"I stand squarely behind my decision," Biden said. "After 20 years, I've learned the hard way that there was never a good time to withdraw US forces."
When he announced the withdrawal in April 2021, Biden said diplomatic and humanitarian efforts would continue in Afghanistan and that the United States would support peace efforts between the Afghan government and the Taliban. He said he had determined that a war that had killed some 2,300 troops and cost more than $2 trillion no longer fit within the pressing foreign policy concerns of 2021.
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