The air-traffic control system is financed by taxes and fees paid by the airline passengers. (I expect the entire system to be privatized in the very near future, as the ATC systems have been privatized in over a dozen other countries.) Most airports also charge passenger fees. Altogether, taxes and fees add about 16% to the price of an airline ticket.
That is a far cry from having the government pick up 50% of the operating costs and 100% of the construction costs of passenger rail.
As for having the government own and maintain the rails—the suggestion makes me cringe. What makes you think that the government can operate a business better than the private sector?
"The air-traffic control system is financed by taxes and fees paid by the airline passengers. (I expect the entire system to be privatized in the very near future, as the ATC systems have been privatized in over a dozen other countries.) Most airports also charge passenger fees. Altogether, taxes and fees add about 16% to the price of an airline ticket."
The ATC system is also financed by fuel taxes paid by private pilots.
Although the Bush administration has been more resolute than the Clinton administration in keeping the ATC system in federal hands, Bush has still waffled. Fortunately, Congress, led by the key committee chairmen, appears determined to reject any attempt to privatize ATC. Thank God. There are so many examples of how privatized ATC is a disaster that it's daunting to even start listing them. To take one (NavCanada), look at how the system is floundering from a technology viewpoint, and how many fatal crashes have been caused by private pilots who didn't want to purchase an instrument flight plan due to the cost.
I'm confident privatized ATC will never rear its ugly head in the US.