Hong Kong, April 29 -- The oil tanker exploded with a ferocious roar, sprouting roiling flames and smoke, before quickly succumbing to the waves near the Taiwanese port city of Kaohsiung. Elsewhere, a few hours later, a Taiwanese frigate hit another sea mine laid near the dual commercial and naval port of Keelung. These events were among the opening gambit of a Chinese invasion of Taiwan.

In fact, belts of sea mines had been surreptitiously laid all around Taiwan, particularly near ports. Sometimes the deed was done by rusty Chinese, but foreign-flagged, fishing trawlers where crews surreptitiously rolled mines into the sea. Others had been stealthily placed by Chinese submarines belonging to the People's Liberation Army (PLA).

Even ear...