This week marks the 26th anniversary of the First Battle of Yeonpyeong, one of the biggest inter-Korean skirmishes since the Korean War and an event that holds important lessons for countering North Korean forces today, according to the man who led the South’s military response.

On June 15, 1999, North Korean patrol boats breached the Northern Limit Line (NLL), the de facto maritime boundary in the Yellow Sea, and initiated hostilities against a South Korean high-speed vessel near Yeonpyeong Island. The ROK Navy responded with calibrated force, sinking a North Korean torpedo boat and damaging several others in a 14-minute firefight.