The choreographed statements by Saudi Arabia and three allies to quarantine Qatar at just after 6 a.m. on June 5 were not signed, but there was no mistake about who was behind them. The move to halt air and sea transport and shut the tiny Gulf nation’s only land border carried the fingerprints of two of the Arab world’s most powerful leaders: Saudi Arabia’s young deputy crown prince, Mohammed bin Salman, and Sheikh Mohamed bin Zayed, the de facto head of the United Arab Emirates. The coordinated action underscores the growing authority of both men, whose countries control vast amounts of oil wealth and buy weapons from the U.S. They’ve been using both to mold the Middle East in recent years by supporting leaders and groups they like and opposing those they don’t. And now they have the explicit backing of President Donald Trump as he tries to toughen […]