U.S. Vice President Mike Pence arrives in South Korea

U.S. Vice President of the United States Mike R. Pence greets U.S. Army Gen. Vincent K. Brooks, United States Forces Korea commander, after landing at Osan Air Base, Republic of Korea, April 16, 2017. Pence’s visit to Korea highlighted the importance of the U.S. – ROK alliance, and how teamwork will be vital to deterring regional threats and maintaining stability on the Korean peninsula. (U.S. Air Force photo by Staff Sgt. Alex Fox Echols III)

U.S. Vice President of the United States Mike R. Pence greets U.S. Army Gen. Vincent K. Brooks, United States Forces Korea commander, after landing at Osan Air Base, Republic of Korea (ROK), April 16, 2017. Pence’s visit to Korea highlights the importance of the U.S. – ROK alliance, and how teamwork will be vital to deterring regional threats and maintaining stability on the Korean peninsula. (U.S. Air Force photo by Staff Sgt. Alex Fox Echols III)

Vice President of the United States Mike R. Pence and his wife, Karen Pence, arrive at Osan Air Base, Republic of Korea, April 16, 2017. Pence is the most senior member of the Trump administration to visit Korea, aiming to reaffirm the ironclad U.S. – ROK alliance. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)

Vice President of the United States Mike R. Pence and his wife, Karen Pence, arrive at Osan Air Base, Republic of Korea (ROK), April 16, 2017. Pence is the most senior member of the Trump administration to visit Korea, aiming to reaffirm the ironclad U.S. – ROK alliance. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)

U.S. Vice President of the United States Mike R. Pence and his wife, Karen Pence, greet Republic of Korea Vice Foreign Minister Lim, Sung-Nam at Osan Air Base, Republic of Korea, April 16, 2017. The visit, which marked the most senior member of the Trump administration to visit Korea, underscored how the long alliance between the U.S. and the ROK is a linchpin of peace and prosperity in the Asia-Indo-Pacific region and the commitment the U.S. government has to support its regional allies. (U.S. Air Force photo by Alex Fox Echols III)

U.S. Vice President of the United States Mike R. Pence and his wife, Karen Pence, greet Republic of Korea Vice Foreign Minister Lim, Sung-Nam at Osan Air Base, Republic of Korea (ROK), April 16, 2017. The visit marks the most senior member of the Trump administration to visit Korea and underscores how the long alliance between the U.S. and the ROK is a linchpin of peace and prosperity in the Indo-Asia-Pacific region and the commitment the U.S. government has to support its regional allies. (U.S. Air Force photo by Alex Fox Echols III)

Vice President of the United States Mike R. Pence walks with U.S. Army Gen. Vincent K. Brooks, United States Forces Korea commander, after landing at Osan Air Base, Republic of Korea, April 16, 2017. Pence’s visit to Korea highlighted the importance of U.S. – ROK alliance, and how teamwork will be vital to deterring regional threats and maintaining stability on the Korean peninsula. (U.S. Air Force photo by Gwendalyn Smith)

Vice President of the United States Mike R. Pence walks with U.S. Army Gen. Vincent K. Brooks, U.S. Forces Korea commander, after landing at Osan Air Base, Republic of Korea (ROK), April 16, 2017. Pence’s visit to Korea highlights the importance of U.S. – ROK alliance, and how teamwork will be vital to deterring regional threats and maintaining stability on the Korean peninsula. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)

Vice President of the United States Mike R. Pence and his wife, Karen Pence, arrive at Osan Air Base, Republic of Korea, April 16, 2017. Pence is the most senior member of the Trump administration to visit Korea, aiming to reaffirm the ironclad U.S. – ROK alliance. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)

Vice President of the United States Mike R. Pence and his wife, Karen Pence, arrive at Osan Air Base, Republic of Korea (ROK), April 16, 2017. Pence is the most senior member of the Trump administration to visit Korea, aiming to reaffirm the ironclad U.S. – ROK alliance. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)

A group of helicopters depart from the flightline during Vice President of the United States Mike R. Pence's visit at Osan Air Base, Republic of Korea, April 16, 2017. The visit, which marked the most senior member of the Trump administration to visit Korea, underscored how the long alliance between the U.S. and the ROK is a linchpin of peace and prosperity in the Asia-Indo-Pacific region and the commitment the U.S. government has to support its regional allies. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)

A group of helicopters depart from the flightline during a visit from the Vice President of the United States Mike R. Pence at Osan Air Base, Republic of Korea (ROK), April 16, 2017. The visit marks the most senior member of the Trump administration to visit Korea and underscores how the long alliance between the U.S. and the ROK is a linchpin of peace and prosperity in the Indo-Asia-Pacific region and the commitment the U.S. government has to support its regional allies. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)

OSAN AIR BASE, Republic of Korea -- U.S. Vice President of the United States Mike R. Pence lands at Osan Air Base, Republic of Korea (ROK), April 16, 2017. Pence’s visit to Korea highlights the importance of the U.S. – ROK alliance, and how teamwork will be vital to deterring regional threats and maintaining stability on the Korean peninsula.