A private contractor would not have sovereign immunity, so you can sue them without the government's assent. They would not receive special legal protections, like the signs the TSA put up threatening you with steep fines if you "verbally abuse" the TSA workers (even police in America don't receive such protection against verbal abuse, but apparently TSA workers do.) If they consistently understaff their security checkpoint, as the TSA routinely does during periods of anticipated heavy travel, the airport could fire them and hire another contractor who can do the job properly.
Airport security in America used to be done by private contractors. The TSA didn't exist before 2001. And before 2001, airport security checkpoints generally ran much smoother and faster than the TSA.
Airport security in America used to be done by private contractors. The TSA didn't exist before 2001. And before 2001, airport security checkpoints generally ran much smoother and faster than the TSA.
(I am not a libertarian, so spare me the jabs.)