While diplomats debated the Fahd peace plan throughout the Middle East, and Arab gulf state potentates met in Riyadh to discuss security arrangements, the U.S. was taking action of quite a different kind last week to buttress the region. The effort involved a long-planned sequence of military exercises in four friendly countriesEgypt, Sudan, Somalia and Omanoccurring over a month's time and involving some 6,000 U.S. personnel. Code-named Bright Star '82, the maneuvers are the biggest trial run yet for the still nebulous U.S. Rapid Deployment Force, which is eventually supposed to have 200,000...

