The near-comprehensive U.S. banking, trade and energy embargo against Iran lifted two years ago by a global nuclear accord will “snap back” into place within six months following President Donald Trump’s decision Tuesday to withdraw from the agreement. In a statement after Trump’s announcement, the White House called the Joint Comprehensive Plan of Action, or JCPOA, a “one-sided” deal that gave Iran a “windfall of cash and access to the international financial system” and only delayed the country’s development of nuclear weapons. The U.S. Treasury Department subsequently updated guidance to set 90-day and 180-day windows for foreign firms to “wind...