It was a late winter night in 1966 and a fully loaded B-52 bomber on a Cold War nuclear patrol had collided with a refueling jet high over the Spanish coast, freeing four hydrogen bombs that went tumbling toward a farming village called Palomares, a patchwork of small fields and tile-roofed white houses in an out-of-the-way corner of Spain’s rugged southern coast that had changed little since Roman times.

In combat, lives can be erased in an instant. Military men and women accept that as a given. But what if peril stalks them as civilians, long after the guns have fallen silent? As the years pass, does the nation bear an abiding obligation to them when they find they face death on the installment plan?