Panamanian authorities have a 1994 bombing’s suspected Iranian-backed Hezbollah mastermind in custody, with a trial ensuing soon. For more than three decades, the mystery of who blew Alas Chiricanas Flight 901 out of the Panama sky, killing all 21 aboard, including 12 top Jewish businessmen and three U.S. citizens, remained unsolved and mostly forgotten by the outside world. The small commuter plane to Panama City exploded July 19, 1994, shortly after takeoff from Colon, leaving only one body in the wreckage, not positively identified for years: a Middle Eastern male thought to have carried the bomb aboard. But now...