U.S. Air Force and Republic of Korea Air Force members pose for a photo at Seosan Air Base, Republic of Korea during Buddy Wing 17-3, March 30, 2017. This training is a Buddy Wing exercise, a regularly-scheduled exercise that occurs several times a year. It is based on realistic tactical requirements and missions expected of our ROK-U.S. combined and joint forces assuming various threats. (Courtesy photo)

U.S. Air Force and Republic of Korea Air Force pilots attend a briefing at Seosan Air Base, Republic of Korea during Buddy Wing 17-3, March 30, 2017. Combined exercises, like Buddy Wing, reinforce the ROK-U.S. alliance and demonstrates one of many alliance capabilities available for the defense of the Republic of Korea. (U.S. Air Force photo/Staff Sgt. Chelsea Sweatt)

U.S. Air Force Maj. Michael Mullin, 80th Fighter Squadron director of operations, goes over a preflight checklist at Seosan Air Base, Republic of Korea during Buddy Wing 17-3, March 30, 2017. Buddy Wing exercises are conducted multiple times throughout the year to sharpen interoperability between U.S. and ROK forces. (U.S. Air Force photo/Staff Sgt. Chelsea Sweatt)

An F-16 Fighting Falcon assigned to the 80th Fighter Squadron at Kunsan Air Base, Republic of Korea, takes off at Seosan Air Base during Buddy Wing 17-3, March 30, 2017. The combined mission demonstrates the strength of the alliance between the United States and the Republic of Korea and their commitment to maintain stability and security on the peninsula. (U.S. Air Force photo/Staff Sgt. Chelsea Sweatt)

An F-16 Fighting Falcon assigned to the 80th Fighter Squadron at Kunsan Air Base, Republic of Korea, lands at Seosan Air Base during Buddy Wing 17-3, March 30, 2017. Members of the 8th Fighter Wing and Republic of Korea Air Force train together as often as possible to ensure the security and stability of the peninsula. (U.S. Air Force photo/Staff Sgt. Chelsea Sweatt)