SOLON, Ohio – Thirty years ago on Oct. 23, Navy Lt. Greg Rosenberg was lying on his bunk when the little corner of Beirut, Lebanon, where he was sleeping exploded with a massive roar.

A suicide bomber had just driven a truck laden with explosives into barracks housing U.S. Marines of a multinational peacekeeping force.

The four-story building collapsed, killing 220 Marines, 18 sailors and three soldiers, wounding another 128 American servicemen....