like an incurring or an isolated incident. what exactly is the white house on the lookout for, david? >> well, that is the problem. you put your finger right on it, which is an invasion's got to start someplace and you don't know when the russians first start rolling whether or not, assuming that they do, whether or not they've got orders to stop someplace. someplace in the east. maybe grab the land around crimea rather than just crimea itself and get that land bridge to russia or whether they would be interested in running all the way to kyiv. so as the west is trying to figure out how to react, you have to have a pretty good understanding of how far the russians are willing to go. and you simply would be unlikely to know that at the beginning. >> at this press conference the president defending the -- defended the u.s. withdrawal f from afghanistan, which many americans saw as a total failure, even though they thought this endless war, as