on a threat to attack forces in the coming days could be even more catastrophic for the u.s. than the scenes we've seen on the outskirts of the airfield so f far, and that's been bad enough. >> the president leaving open a little wiggle room on august 31st, but the taliban making it clear today, they do not see it that way. sam kiley live for us at the airport in kabul. thank you. other major news this mor morning, source tells cnn the fda could grant full approval for pfizer's coronavirus vaccine as early as today. till now, the shot has been administered under an emergency use authorization. the approval could help get the vaccine to more people. cnn's elizabeth cohen joins us now. what are we hearing, elizabeth? >> john, in some ways this doesn't make a difference, right? this was a shot you and i got that was approved after 40,000 people took it -- authorized, i should say, given emergency