In the wake of Hurricane Maria, you probably saw those pictures of shipping containers stranded at United States ports, waiting to be delivered to survivors in Puerto Rico.

One of the reasons it is so difficult to get relief supplies to hurricane victims is a 1920 law that was designed to promote a civilian merchant marine fleet that could “serve as a naval or military auxiliary in time of war or national emergency.”

This Merchant Marine Act, otherwise known as the Jones Act, requires that all goods shipped between United States ports must be transported by United States ships manned by Americans. So a foreign ship carrying cattle from say, Los Angeles to Tokyo, would be forbidden from stopping in Hawaii along the way.

This policy is great for American shipping companies, but it is terrible for American consumers in remote places like Alaska, Hawaii, and Puerto Rico. One economist estimates that the Jones Act has cost the Puerto Rican economy $17 billion over the past 20 years alone.

It has become routine for presidents to waive the Jones Act in the wake of natural disasters. President Bush waived the Jones Act after Hurricane Katrina, and President Trump waived the law after Hurricanes Harvey, Irma, and eventually Maria as well.

But the president shouldn’t have to waive this World War I-era relic after every natural disaster. The United States has long had an adequate navy that can provide for national security without an auxiliary merchant marine force.

It is long past time to repeal the Jones Act entirely so that Alaskans, Hawaiians, and Puerto Ricans aren’t forced to pay higher prices for imported goods—and so they rapidly receive the help they need in the wake of natural disasters.

That is why I joined with Sen. John McCain (R-AZ) this week to permanently exempt Puerto Rico from the Jones Act. American Samoa, the Northern Mariana Islands, and the U.S. Virgin Islands are exempt from the Jones Act already. Puerto Rico should be, too.