In some areas of Europe and the U.S., ships have been required by law for years to use low-sulfur fuel when in port.

CNN: Shipping looks to clean up its act

He could encourage and sign into law legislation barring foreign ownership or management of U.S. port facilities (akin to the rules governing other critical infrastructure).

CENTERFORSECURITYPOLICY: Freedom Flame 2013

Until there's a law, Addax cannot build the pipeline that would probably move oil to the Turkish port of Ceyhan.

FORBES: Magazine Article