At a principals’ meeting on November 8, 2001, CIA Director George Tenet said: ” ‘The Iranians may have switched sides and gone to side with the Taliban.’ Iran, one of the biggest supporters of the Northern Alliance before September 11–in conjunction with the U.S., Russia and India–was now worried that the United States might gain some kind of foothold in Afghanistan. Sensitive intelligence showed that the Iranian Revolutionary Guard, the radical element that held real power, was shipping weapons to the Taliban, and that it was reaching out to al Qaeda. Some al Qaeda were using Iran as a transit point out of Afghanistan into places like Yemen.”
– Bob Woodward, Bush at War, Page 298