According to the United States Department of Transportation's Bureau of Transportation Statistics, rail and mass transit are considerably more subsidized on a per passenger-mile basis by the federal government than other forms of transportation; the subsidy varies year to year, but exceeds $100 dollars (in 2000 dollars) per thousand passenger-miles, compared to subsidies around $10 per thousand passenger-miles for aviation (with general aviation subsidized considerably more per passenger-mile than commercial aviation), subsidies around $4 per thousand passenger-miles for intercity buses, and automobiles being a small net contributor through the gas tax and other user fees rather than being subsidized.[78] On a total subsidy basis, aviation, with many more passenger-miles per year, is subsidized at a similar level to Amtrak. The analysis does not consider social costs and benefits, or difficult to quantify effects of some regulation, such as safety regulation.
Amtrak is much more subsidized and less effective then other modes of transport. Republicans dont like it because its inefficient and a waste of money.