Please see the source for the video.
The US early Wednesday, April 26, began moving the THAAD missile defense system to central South Korea opposite the border with the North – months ahead of schedule. A South Korean military official said two road-mobile launchers had arrived at the Osan Air Base. One THAAD (Terminal High Altitude Area Defense) unit includes six launchers.
…
Later Wednesday, all 100 US senators are scheduled to gather at the White House for a briefing by US security and military chiefs on the North Korean crisis, as the buildup to meet North Korean belligerence continues apace.