Across the Lowu railroad bridge into Communist China one morning last week bustled the everyday traffic from Hong Kong: pongee-clad farmers hauling produce, old women bent double under sacks of flour, visitors with gifts for relatives on the mainland. By mid-morning 200 travelers had crossed the frontier, and one of them was carrying a lethal parcel. Then, as the line shuffled through Red China's wooden customs shed, a powerful blast splintered the building, killed an inspector and a woman traveler, injured 27 others.
Red reinforcements rushed to the border and sealed it off while they rounded up 500 suspects.
In 13...