China's Smoke Signal

IN WHAT AMOUNTS TO AN OBSCENE GESTURE TO THE rest of the world, China exploded a nuclear warhead with a yield of 1 million tons of tnt at its underground test range in far northwestern Xinjiang province. It was the largest such blast the Chinese have ever detonated and far bigger than the 150-kiloton testing limit the U.S. and the former Soviet Union have been observing under a 1974 agreement.

Chinese officials confirmed that the explosion was for military purposes, but then blandly added that Beijing's testing program has "exercised restraint" to conform with the government's "basic position for complete prohibition...