MEANWHILE, BACK ON THE CHINA-NORTH KOREA BORDER: The U.S. Acting Assistant Secretary of State Susan Thorton quoted Chinese officials as saying they have “tightened border inspections, beefed up policing on the border and stepped up customs inspections.”

However, Ms. Thorton added: “Their calculus about how much pressure to impose on North Korea is related to their tolerance for potential instability, which is low, I would say.”

Someone needs to remind Beijing that a nuclear war on the Korean peninsula will create actual instability.