In the hall of fame for government waste, they should reserve a room - or perhaps a whole wing - for Amtrak.

The numbers on Amtrak National Railroad Passenger Corp. are astonishing. In fiscal 1978, the government will pay about $650 million to subsidize Amtrak's trains. Since its start in 1971, Amtrak has swallowed almost $3.4 billion in government funds or government backed loans. By 1982, annual subsides will approach $1 billiob - even of the system is scaled back as proposed by the Transportation Department. Ticket revenues now cover only about 37 cents of every dollar in costs.

For this colossal outlay, Amtrak has performed very little social good. On many routes, it provides massive subsidies to middle and upper middle-class travelers. On the New York to Miami run, it subsidizes the average trip by about $122. Despite the mounting government aid, service has generally deteriorated. Nearly one-third of the trains regularly arrive more than 10 minutes late, a record worse than two years ago.

Nor is that all. Running with many empty seats. Amtrak probably wastes energy. Even if it doesn't, the potential for reducing energy use, pollution or congestion is small. Last year, Amtrak provided less than 1 percent of intercity travel, about a third that of buses and tenth that of airlines. Finally, by subsidizing competition to buses. Amtrak has hurt that industry's profits and encouraged bus owners to seek federal subsidies exceeding $100 million. Subsidies thus beget subsidies.

If nothing else, Amtrak stands as a shining example of the government's inability to eliminate wasteful programs. Trains enjoy an undesered fashion. Their supporters refused to ask the question: why should the government pay so much for so little? Amtrak survives on nostalgia, sheer inertia and muddled analysis that blames its problems on mismanagement.

Whatever mismanagement exists, the genuine source of Amtrak's failure is more fundamental. Trains simply cannot compete - in time, cost or travel flexibility - with planes, buses and automobiles. Business executives won't trade two hours on a plane for a day on a train. Family vacationers usually need their cars: even if they don't train travel generally costs families more than car travel.

These simple realities explain why Amtrak was doomed from the beginning and why is continuation means throwing more good money after bad. To establish genuinely first-class service would require untold billions in track improvement, new equipment and more frequent trains. But most Amtrak trains don't cover their operation costs. To run more trains is to lose more money. Congress won't pay for that, but it has neither the version nor the courage to embrace the logical alternative - put Amtrak out of business.

Ending programs like Amtrak ought to unite liberals and conservatives: liberals because they want to channel government dollars to more socially useful programs: conservatives because they want to squeeze government spending.

But, if fact, the political process does not work that way. The average Member of Congress - what ever his or her ideology - recoils at the incendiary idea of axing a whole program.

The political pains and pleasures don't balance. The federal budget has now grown so large (about $500 billion in fiscal 1979) that many otherwise sizable programs get lost. Often, the only people who know about spending cuts are spending benefisciaries. And no Member, as one aide said, "likes to cut services for his district."

Moreover, congressional courtesy being what it is, most Members defer to the the recommendations of the relevant committees. Agencies pander to the key committee leaders. Amtrak simply runs trains through their districts, a practice best epitomized by the trains that run through West Virginia, home of Rep. Harley O. Staggers, chairman of the House Interstate and Foreign Commerce Committee.

Consequently, efforts to cut spending often take forms that are economically inefficient but politically painless. One trick is to reduce big-ticket purchases by the Pentagon such as cutting the number of new fighters from 100 to 30. This saves money in the current year, but usually increases the government's ultimate costs. The extra planes are bought later, lengthening production runs and raising unit costs.

Another trick is to demand across-the-board cuts for an agency. The House, for example, recently mandated that the Secretaries of Labor and Health. Education and Welfare reduce their "controllable" spending by 2 percent below congressional appropriations. This approach allows Congress the twin pleasures of voting for both higher and lower spending.

Congress has treated Amtrak with characteristic ambivalence. When subsidies surpassed $500 million (up from $40 million in 1971), it made slight reductions, but when Amtrak said it might discontinue that and voted supplemental appropriations.

The sad thing about Amtrak is that train service has probably declined in the one area where it might be justified: the Northeast corridor. In the Northeast, population centers are large, inter-city distances are short and auto and air congestion are high. In fiscal 1977, these trains accounted for 57 percent of Amtrak's ridership, 31 perceng of its revenues and only 24 percent of its costs. Unlike most other Amtrak trains, most of these actually cover operating costs (but not fixed investiment expenses).

But to think that Congress might limit Amtrak only to the Northeast is to forget logrolling. Members outside the Northeast won't vote for the Northeast unless they have something for their own districts. Not surprisingly, Transportation Secretary Brock Adams's preliminary "reevaluation" of the Amtrak system - a final plan is expected by December - still would allow for a nationwide railroad system with a spiraling subsidy bill.

Adams conceded that Amtrak "spend large amounts of money" for a "relatively small segment of the traveling public." But he rejected ending Amtrak, saying, "There is a significant constituency for maintaining Amtra . . .even among people who today do not frequently use it." That's a statement worthy of a former six-term Member of Congreses.