The devastation in Puerto Rico from Hurricane Maria is awful to behold, and the Trump Administration will have to mobilize more resources to help. Here’s one idea: Suspend the law that raises the price of sea-borne energy and food shipments to the island.

We’re talking about the Merchant Marine Act of 1920, better known as the Jones Act. The law requires that goods transported between U.S. ports be shipped on vessels built, majority-owned and manned by Americans. Think of it as a legally sanctioned shakedown for U.S. shipping...