Then why doesn't the Northern VA/Washington DC governments/populations pay for it themselves? I mean, it must be going to pay for itself, no? After it's built with federal tax dollars (and I'm to the tune of six-figures/yr), if it turns a profit, who gets the proceeds?
It's not going to turn in a profit. No mass-transit system in the nation is self-sufficent.
Because NoVA's gasoline tax money was siphoned off and stolen to pave every cow path downstate.