The threat to global trade in the Red Sea remains high, even with efforts to protect commercial vessels from attacks by Iranian-backed Houthi militants based in Yemen. Danish shipping giant Maersk’s decision on Tuesday to pause Red Sea and Gulf of Aden transits until further notice underscores the difficulty for the U.S.-led initiative, called Operation Prosperity Guardian. U.S. Navy helicopters, returning fire, sank three of the four Houthi boats that attacked the Maersk Hanzghou over the weekend, the U.S. military said.