and the u.s. official telling us they are concerned that russia will start attacking the supply routes across ukraine as the weapons come in through the polish border and are taken east to donbas. the worry is the russians will attack those supply routes. the first question is why haven t they done it already as far as we know, and we re told, you know, the russians don t have the best intelligence on it and these are mobile targets, truck convoys, moving railcars, not something that the russians are very good at targeting. but with this vast amount of new weaponry moving in, and now the fight for the donbas on, there is concern that the russians will move to try and hit these supply convoys to make the ukrainians less successful in being able to challenge the russians. this is going to be an armor and artillery fight out in the east to a very large extent. bianna? and the russians warned as much by sending that official letter to the u.s. last week.