I got back from a fun week in Mexico and encountered extremely heavy security IMHO:

my trip report about Oaxaca:
http://www.flyertalk.com/forum/Forum81/HTML/002331.html

To sum up, they thoroughly searched our luggage and carry-ons. On one leg, they did it twice. Besides the usual careful checking of pax, tix and passports three times and the metal detectors, they wanded virtually every pax a second time at the gate.

All these employees doing this checking were private.

I am very distraught about this bill having passed and its implications, a growing new federal workforce. Private contractors can always do a better job given proper incentives and oversight.

The USA has a very safe food supply and you could make the same argument that "food is too important to leave to the private sector because they always just want to cut costs" and you can end up with federalizing everything.

The reality is that security is in everyone's interests so that there are no more incidents. Incidents are bad for business.