The U.S. Army announced this week it wants a new generation of rugged, wireless speakers for its psychological warfare units. An earlier version of the loudspeakers on the U.S. Army’s Special Operations Command’s wish list would likely be familiar to former Panamanian leader Manuel Noriega. In 1989, the U.S. Army blasted hard rock outside the Vatican embassy in Panama City where Mr. Noriega had taken refuge after 24,000 U.S. troops dropped in to arrest him five days before Christmas. In the end, it wasn’t psychological warfare, but old-fashioned street protests from Panamanians that led Mr. Noriega to surrender to U.S....