U.S. seaport operators are asking for extra time to implement pending tariffs on towering ship-to-shore cranes as they expect President Donald Trump's administration to follow through on a promise to essentially ban that vital cargo-handling equipment. The United States Trade Representative (USTR) earlier this year proposed tariffs of up to 100% on those cranes after China devoured market share in its bid to dominate maritime manufacturing as well as commercial and military dominance on the seas. China, via state-owned Shanghai Zhenhua Heavy Industries (ZMPC), now commands the global market and has supplied some 80% of the ship-to-shore cranes in the United States.