they could decapitate the control of the ukrainian forces quickly. the first few days, this has not happened. >> reporter: smaller tactical errors have happened like allowing ukraine's drones to hunt freely. >> very frsurprising considerin the efforts haven't neutralized and the troop on the ground seem oblivious to the fact they were being targeted. >> reporter: russian forces may be holding back trying to take big cities with lighter forces hoping to inflict minimum damage. ukraine's resistance could trigger a switch to what is russia's traditional military doctrine, overwhelming force. >> you're pointing to a scenario where there will be far greater blood shed. it's a calculation about how brutal they are willing to go. they lost the political ability