$860 million a year is insane.
$860M. Say 5000 marshals, and an equal number of support people including trainers, admin, contracts, and so forth comes out to $86K per person. Add in training costs, health care, insurance, and so forth and per agent it’s not too much to have an armed person on the plane. Yeah, the pilot can open the cockpit door and get attacked if he wants to, and we can fantasize about armed passengers and ninja flight attendants, but realistically the only way we have now to get a guy with a gun legally on a flight is the air marshal program.
It probably costs less than putting 5000 cops on the street of a major city.