Bush 43's... or maybe Darth Cheney's. In the hysteria after September 11, 2001, they felt they had to "do something," and invading Afghanistan was "something." By itself it wasn't a bad idea. Bin Laden probably had nothing to do with the Twin Towers, but he took credit for them, and the initial invasion chased him and al Qaeda and the Taliban out of Afghanistan. They should have quit then, but American donors decided they wanted the trillion dollars worth of minerals locked up in undeveloped, roadless places. The American people loved it, but were soon watching Iraq and forgot about Afghanistan, allowing the MIC to start their 20-year long war. I don't blame Bush for the problems encountered in the withdrawal, but blame the Pentagon and all high ranking Army officers. The Pentagon should have had detailed contingency plans for withdrawal, constantly updated, from the moment we decided to send Special Forces troops into the country. This was especially true after Trump started negotiating with the Taliban. I'm pretty sure we have contingency plans to invade Mexico, Canada, and Fiji. It used to be we had contingency plans for every conceivable event. There were giants in the land in those days /sarc.