With tensions between the U.S. government and North Korea at a historic high, the Department of Defense spent 2017 deterring an armed confrontation with Kim Jong Un’s regime on the Korean peninsula. The Pentagon deployed three carrier strike groups to the Western Pacific for the first time in a decade; stood up THAAD missile defense batteries in South Korea; and deployed squadrons of F-22 and F-35 fighter jets to patrol the skies near Pyongyang. All the stakeholders know that, even with overwhelming U.S. might and decades of wargaming, an invasion involving the 28,500 U.S. troops currently stationed in South Korea could bring massive casualties for military personnel and civilians, including an estimated 20,000 South Korean deaths a day from North Korean artillery.