For years, critics of the Jones Act have made the same promises: Repeal the law, allow foreign vessels into domestic trade and American consumers will see lower prices and stronger supply chains. Now the real-world test case is underway, and it is failing to make a difference. Even as policymakers of both parties agree on the need for robust American border security, the Jones Act waiver has blown a hole in America’s largest border — 95,000 miles of coastline — opening it up to foreign vessels and foreign crews who don’t comply with U.S. immigration, tax, labor or other laws. The result is harm to American homeland security and to a strategically vital American industry, with zero benefit to the American consumer. The Jones Act reserves domestic maritime trade for American-built, American-crewed and American-flagged vessels. This creates a stable market signal for investment in vessels and crew dedicated to serving U.S. needs.…