Exceptionally high revenues, particularly from war aid for Russia, are consolidating the power of North Korea's autocratic leader. A small number of people in the country are benefiting from an economic boom.

North Korea's economy is booming but North Koreans see few benefits. Kim Jong Un is the big winner and is taking credit for growth that Russia and China have facilitated.

Exceptionally high revenues, particularly from war aid for Russia, are consolidating the power of North Korea's autocratic leader. A small number of people in the country are…