jennifer griffen is at the pentagon for what this means for the military. first up, john roberts joining this along with us. good evening to you, john. >> reporter: martha, bret, good evening to you. an hour and a half before the president spoke we spoke with senior administration official who's put more context to what the president was about to say. the main driving force of what the president revealed tonight is to try to convince the taliban they cannot win on the battlefield and they're only hope of surviving is to come to to the table and negotiate some sort of political settlement with the government in kabul. at the same time it looks like the united states can't win decisively on the battlefield ever. listen to how the president put it a short time ago. >> some day after an effective military effort perhaps it will be possible to have a political settlement that includes elements of the taliban in afghanistan but nobody knows if or when that will ever happen. america will continue its support for the afghan government and the afghan military as the