Well, I can tell you from my SO who is in charge of one level of airport screening, ticketing and security at a major US airport that if any potential passenger threatens any of the staff in any manner (call them a “Bitch,” “Bastard,” “Fuck Head,” etc.) and then do anything else contrary to the posted regulations at security, your chances of flying out that day from that airport are virtually zero.
They had a woman just today ignore repeated warnings about entering an airport concourse from the exit area (where arriving passengers leave the secure concourse and enter the main public airport area) just to give her daughter one last hug – who had already entered the secure zone. The woman had walked passed several large (2’x3’) warning signs and barriers.
The lady was told to stop and leave immediately or she would be arrested and handcuffed on the spot. The woman stormed off calling everyone, “You’re all a bunch of fucking idiots,” to which my SO replied out loud, “We may be but at least we can read the signs!”
The departing passengers waiting in lines to enter security gave the security staff a rousing applause.
The hard part travellers seem to not understand is airport security are given little leeway when it comes to maintaining security. They must follow FAA regulations and the new security laws without favor or bias – meaning the laws/regulations cut them no discretionary slack. If your argue or really be stupid and actually “threaten” airport security staff, you can be arrested for making terrorist threats.
Notwithstanding Fourth Amendment search and seizure, your privacy rights are balanced against the security concerns of everyone else who is flying. Also, too, you are provided with sufficient warnings before you purchase a ticket when you book a flight, at the gate and at security. Yet people still show up at security carrying objects that are subject to confiscation. (Keep in mind that you are paying a private commercial carrier to transport you, and not the government. As such, carriers can impose restrictions, including searches, where the Fourth Amendment may have no protection for you. I’m still trying to get a clarification of this part from lawyer friends so don’t come down on me for it.)
Once you enter the secure areas of an airport you are subject to search at any time, as well as being subject to all the same laws/regulations you had to pass in order to get through security. For example, depending upon changing conditions if you enter security with the maximum two carryons, go to your gate, sit and wait (and in the process readjust your carryons to now have more than two in hand when time to board) you may be denied boarding at the gate. Hassle the airline boarding staff at that point and kiss goodbye your flight out that day, too.
Geez, it all sounds so fascist, and it very well may be. Yet my SO says that they find every day potential passengers deliberately attempting to smuggle board guns, knives, box cutters, razors, etc. Is it any wonder the slightest provcation will get you an extended search?
I don’t envy her in the job: No leeway with the law/regulations. People trying all the time to circumvent security, trying to smuggle things aboard planes, and worst of all being verbally harassed and threatened by potential passengers and their non-flying friends/relatives.
No wonder she is looking to find a better job, even after the raisies she received to stay. No wonder her staff turnover is worse. I know my SO does the best she can because for every nasty potential passenger episode, another ten passengers compliment her on her demeanor and professionalism at such a tough, crappy job. Unfortunately compliments cannot pay bills. 
I’m sure the next hijacking/terrorist attack that occurs though our airport system will be blamed on airport security. However, from hearing details firsthand of what really goes on, I’d lay much of that blame on a flying public who thinks every passenger is unique and not subject to the security laws and regulations.