One of our favorite transportation facts concerns the difference between U.S. Route 1 and Interstate 95. They both run between Maine and Florida. Why is one a U.S. Route and the other an Interstate? What is the difference between these two kinds of national highways? The answer, it turns out, is that they come from different authorities under the Constitution. The founders delegated no specific authority to Congress or anyone else to build roads. When the problem came up, it was decided to use the authority to operate a postal service. So the old U.S. routes are post roads. When it came to a project as big as the Interstate system, however, a different authority was tapped — namely, the defense authority. The interstate highways are national defense highways.

We found ourselves thinking of this distinction in trying to puzzle out what should be done about Amtrak. What is the constitutional logic of the federal government operating a railroad in the first place? As with most federal programs today, the question isn’t something to which the government is giving consideration. Amtrak was established by the Rail Passenger Service Act of 1970, in which Congress removed from the nation’s private railroads the burden of carrying unprofitable passenger traffic. Instead of creating a government agency to run the trains, however, Congress created a “for profit” — no joke — entity, incorporated in Washington, D.C., and under Congressional oversight. The statutes that authorize Amtrak cite justifications such as the need for — again, no joke — “modern, cost-efficient, and energy-efficient intercity rail passenger transportation,” but cite no authorization for such a venture in the Constitution.

Since Amtrak’s creation, Washington has tried to distance itself, claiming that Amtrak is separate from the federal government — though the Supreme Court disagreed in 1995 when it ruled that, at least for First Amendment purposes, Amtrak was an “agency or instrumentality of the United States.” But no one has ever legally challenged the fundamental legitimacy of the federal government establishing Amtrak, and maybe no one ever will. Congress, though, should keep Amtrak’s curious status in mind as it cleans up the financial mess the agency has created over the last 30 years. Why preserve a money-hemorrhaging federal rail system when smaller, more profitable lines could run independently, and constitutionally, either in private hands or as cooperative ventures between adjoining states? The Northeast Corridor as well as a number of West Coast routes could likely thrive under a new system. And the federal government could stop exercising a power not enumerated in Article I, Section 8 of America’s Constitution.