Under a hot Caribbean sun at 3 p.m. one day last week, stevedores on Havana's eastern waterfront bent to a task of No. 1 priority in Fidel Castro's Cuba. In the holds of the 4,310-ton French freighter La Coubre, were 76 tons of Belgian artillery shells, grenades and small arms ammunition. Most of it never reached its destination. At that hour, a shuddering blast rocked the vessel, hurling exploding shells, steel deck plates and human fragments aloft in a pillar of fire.
A second munitions ship quickly cast off, was towed out of the danger area. Firemen worked close to the burning...