J oe Picard perched atop a precarious mound of 300-plus-pound high-explosive shells as his ship churned toward Normandy’s beaches. The teenager had been at sea only once before, to cross the Atlantic, and now he was sailing across the English Channel to pile into the breach that Allied forces had opened in Hitler’s defenses weeks earlier, on D-Day. Smoke from the fighting still rose on the horizon, but Picard’s eyes scanned the gray water below for signs of German U-boats. “You know,” he told