reporter: that s right. the number two at the cdc says limited testing and delayed travel alerts with europe helped drive the outbreak in the u.s. 2 million traveling from italy and other european countries in february. the ban didn t start until march 11th. she wrights, we clearly didn t realize the full import of this. david? tom, thank you. president trump is sharpening his criticism of china, after a u.s. intelligence report found china hid the severity of the outbreak and then hoarded vital medical supplies. so will the u.s. take action? here s jonathan karl. reporter: to president trump, there is no doubt who is to blame for the coronavirus pandemic. it came from china. it should have been stopped. it could have been stopped on the spot. they chose not to do it, or something happened. either there was incompetence or they didn t do it for some reason. and we re going to have to find