With metalwork following 2 hip operations, I am always subjected to intimate searches in public after I go through the scanner. Last time I flew, the entire contents of my cabin baggage was scrutinised. Good thing I wasn't in a hurry for the plane. But coming back from a foreign destination, I was waved through the screen when I indicated my hips because they trusted my explanation. Besides, there was a rapidly forming queue which caused them a bit of panic. So if you can't trust security overseas, why isn't there more cooperation and coordination over security needs? Is it solely an airport management issue, or is there a need for an international body to set standards? If there is one, I am unaware of it.

First, the point of most security measures anywhere is to dissuade; the appearance of security is a preventative.

Second, obviously a committed terrorist or lunatic can get through security. Problem is chance. Consider it like this: a person is trained for a period of time, possibly years, and then is sent through airport security. Maybe security will miss him or her, maybe not. The terrorists can't know so they have to decide to risk a substantial investment in plans, time, organization when maybe the person gets caught at a scanner or pat down.

In blunt terms, we rather naturally take the failure on a test to mean anyone can walk through security and thus the entire thing is a sham. Not true. As long as there is a reasonable chance of getting caught, as long as no one knows if the scan operators are better trained, etc. then security functions as a deterrent. We don't know the exact details of the test so maybe it was a solid test in which a trained agent worked to disguise a firearm.

The alternative idea is in fact kind of ridiculous: having security everyone believes is impregnable. That can't happen and if one believes security is then that leads to over-confidence, lack of improvement in methods and lack of meaningful testing. Imagine if they only tested in the assumption they caught everything. That would make security truly a sham.

@jomiku:
I would disagree that security (no mater how inhanced or technologically backed) functions as a deterrent. A person who is willing to commit a suicide mission, will not be dissuaded by tight security. It may act as a deterrent on the organizers of such acts, cause then they'll have to calculate if so much time and resources is worth investing for a possibly failed mission (as you already mentioned). As for the person commiting the act, I don't think those persons think that much ahead....

Rather than being aghast that Americans with guns have gotten through "security", let's look at the bright side: Despite it being "not uncommon" for Americans to take guns on planes, no one has used one for any criminal purpose. Perhaps "security" procedures are indeed ridiculous, but their failures show us that the threat they are supposed to protect us against is ridiculous as well.

TSA and Homeland Security seem to believe security "theatre" is effective as a deterrent. Perhaps, but real security in the form of catching a culprit in an attempt at breaching the system is far more effective.

You can't tell how effective any security procedure or device is unless you try to subvert it at a known rate, and measure the success rate of discovery. [Mathematicians call it Bayes Theorem, and it permeates many fields.] So at least TSA is trying to measure effectiveness.

Alas, their own documents suggest that screening is near useless. Their watch and no-fly lists suggest a significant fraction of travelers are active terrorists. If true, the system should be catching measurable numbers of them. It isn't. So Bayes Theorem has three explanations:

1) TSA screening isn't effective, and thousands of terrorists are regularly penetrating their security with little fear of detection.

2) There aren't anywhere near so many terrorists (probably less than 5%) as Homeland Security would have you believe.

3) Both the screening and watch lists are ineffective.

Take your choice. Screening doesn't work, we haven't a clue who the real terrorists are, or the whole exercise is a waste of money and effort.

If the subversion/detection rate is known, Bayes Theorem can tell you which is correct. I suspect TSA and Homeland Security have the answer, don't like it, and are covering up their own ineptitude.

After all, an entire bureaucracy is at stake here, and we wouldn't want them to be fired for not doing their job properly would we?

I honestly wish i could say "I am surprised" however, knowing the attitude the clerks and X-ray readers have, I am not a bit surprised. my story goes like this; the day after Thanksgiving 2010, I am heading to Singapore on work related matters, emotional departure day, to leave my family behind on such day; upon arrival at the security check, I had a female agent say something to me that i unfortunately could not decipher; I asked her if she was talking to me because I could not understand a word; she became "a monster" and charged at me like I was some kind of outlaw, after a few minutes I saw the rest of the cavalry come to the rescue and I was thoroughly humiliated for no reason or knowledge of a law I had broken; it took the agents 25 minutes to check all my personal and body parts; in the meantime, other fellow passengers just walked right through w/o a care in the world -- surprised, I am not.

Don Vito
I'm not surprised. I often have trouble understanding what officials in the USA say to me.

This should be the last straw as far as the traveling public putting up with the "Whole Body" scanners and their obvious and not-so-obvious health hazards of ionizing backscatter radiation. And if the screeners are so careless as to let guns through, what assurance to we have they are competent enough to properly operate these machines so we really don't get fried with a super-dose of X-rays?
The whole pretext for installation of the scanners - the Flight 253 "Underwear Bomber" was a false-flag operation to begin with. There was a huge contract waiting in the wings that took just this type of incident for Homeland Security to purchase - making hundreds of millions of dollars for the manufacturer. Inculcating a false sense of security is totally counterproductive. Take the advice of the chief of security at Ben Gurion International Airport and get rid of these scanners NOW!