great day to be here. >> meghan: me too. let's begin. it's not every day that the senate is asked to attend a briefing on matters of national security which underscores the urgency by which the trump administration is trumping the threat posed and threats of more nuclear tests. that briefing taking place at the white house tomorrow. all this after missiles pull into a south korean port after we hear that north koreans are conducting life fire drills. the submarine will join the aircraft carrier strike group in japan. senator lindsey graham will be one of the lawmakers at tomorrow's briefing. he believes the u.s. must be prepared to launch a preemptive strike as a last resort. he met with president trump last night and had this to say this morning on "america's newsroom"" >> i had dinner with the president last night. it was a great dinner. i'm really impressed with his