More than a dozen Latin American leaders joined the U.S. president to launch a new security initiative, called ‘The Shield of the Americas’ in Miami.DORAL, Fla.—U.S. President Donald Trump on March 7 welcomed his Latin American allies to Florida for a summit focused on addressing regional issues and announced a new military coalition to combat drug cartels in the Western Hemisphere. “On this historic day, we come together to announce a brand new military coalition to eradicate the criminal cartels plaguing our region,” Trump said as he began his remarks at the summit. He said that the new partnership, called...