You can't just go around running expensive government programs on the basis of there being no proof that they don't help, that would lead to an infinite number of programs and a huge disincentive to run those studies.
It’s flying bus that a) can be rather easily converted to a missile, and b) is sealed until it touches down so any craziness is locked in for hours possibly.
I’m more comfortable as a flyer and as someone who’d like to do business in the US if I know that there are air marshals. Surely this pays for itself this way, especially given the ever increasing accessibility of air travel. I say this an American who knows how crazy our population can be.
