There is something about Amtrak — perhaps the romance of railroads or the promise of relieving traffic congestion and economizing on oil and greenhouse-gas emissions — that causes otherwise sensible people to lose contact with reality. The reality is that Amtrak has been a waste of taxpayer money since its creation in 1970. It doesn’t significantly reduce congestion, fuel use or greenhouse gases. Amtrak is too small to have any appreciable effect in any of these areas. Yet it retains an aura of respectability with much of the public and many “experts,” who believe it should survive and, perhaps, expand.

The latest example is a report from the Brookings Institution, one of Washington’s premier think tanks. The report points out that Amtrak’s 2012 ridership of 31 million was a record and that some of its most heavily traveled routes have an operating profit (what Brookings calls a “positive operating balance”). Amtrak is undergoing a “renaissance,” said Brookings. It adds: “Passenger rail is a vital component of the country’s national transportation network.”

Actually, it isn’t.

To see why, dissect that historic ridership of 31 million. The number looks impressive, but on any given day, it’s about 85,000. Not much. Even if it doubled, it wouldn’t be much. Domestic airline passengers total about 650 million annually; that’s 1.8 million a day. More important are the 140 million Americans who commute daily to work, about 85 percent of whom drive. And then there’s personal, vacation and pleasure driving.

If Amtrak vanished, hardly anyone would notice except Amtrak’s workers and its small number of daily riders.

Before World War II, intercity rail passenger service flourished. But postwar changes caused rapid decline. Air travel was faster and cheaper for long distances. Suburbanization hurt shorter trips, because travelers usually needed cars to get to their final destinations. Passenger losses mounted for railroads, imperiling their essential freight operations. In 1970, Congress allowed the railroads to abandon intercity passenger service by creating Amtrak, which would become profitable by preserving the most promising routes. That was the theory.

It hasn’t worked.

Still, it can be argued that some passenger trains should be saved if they can pay their own way. The Brookings report notes approvingly that some heavily traveled routes — led by the Northeast Corridor between Washington and Boston, which represents about half of Amtrak’s revenue — more than cover their operating costs. In 2011, the surplus was a hefty $205 million, says Brookings.

The Brookings study inspired media stories suggesting that Amtrak might be profitable if it dropped its losing routes. Amtrak’s problem, according to this view, is that it must include many uneconomic long-distance trains — for example, the California Zephyr from Chicago to San Francisco — for political reasons. Legislators from other regions wouldn’t support train service confined mostly to the Northeast. Most long-distance trains have big operating deficits. In 2011, the Zephyr’s was $63 million.

The trouble is that “operating” costs is a limited concept. It covers labor and fuel expenses of running trains but excludes many other costs: most importantly, Amtrak’s costs of acquiring passenger cars and locomotives, and also major improvements to tracks and bridges. It’s unclear whether any Amtrak routes would be profitable if all costs were included. Amtrak’s annual federal subsidy has recently totaled about $1.5 billion.

Amtrak is a prime candidate for the budget guillotine. Deficit reduction should focus on programs that are unneeded, ineffective or wasteful, lessening the pressure on more valuable activities — say, scientific research, border patrols, Head Start and others. Choices need to be made. Sure: If some Amtrak routes can stand on their own, let them be privatized. Sure: If states and localities want to subsidize rail projects — including high-speed rail — let them. After all, the benefits of most transportation projects (roads, mass transit, rails) are local.

But the federal government should leave the train business. And it is a business, not a public service, because private markets already provide what Amtrak is selling. Almost anyone riding Amtrak can find other ways to travel (car, plane, bus). The fact that a program so weak has so many defenders is yet more evidence why our budget debates are stuck.

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