So many people are throwing in their 2cents (which given their lack of knowledge of the technology etc, is telling as it's really only worth next to nothin') on this that it's depressing. And they have to nerve to say 'And these people run our government?!' Well duh, politicians come from the same population as them. Voters can be politicians and politicians vote too.
Anyhow it's so stupid to compare this to cell phone usage. Cell phones are up against the head. The Rapiscan machines have a bit more of an air gap and are TeraHertz not Mega or GigaHertz.
Our bodies can generally handle the naturally occurring radiation when 40,000ft up in air on a 6 hour plane ride. Thing is that it's the duration, it's spread out of the length of cruising altitude flight. However the Rapiscans are a huge burst in 1/360th of the time. Not good. Like putting your body through a hot tub versus getting a big bucket of boiling toxic water splashed on you in a few seconds.
The former head of DHS Michael Chertoff (the first one appointed by Bush) was behind this company that pushed the scanners to airports. Originally they were for high risk areas such as prisons and diamond mines etc. But some sales evil genius started getting them into airports (bigger markets) and the Underwear (non-)bomber was a convenient reminder that 'terrorists are always looking for ways to blah blah' and voila!
So if you want your DNA heated up and split then g'head, get all the nudey scans you can muster the patience to put up with.
Love how they're called Rapiscans, pronounce it 'rapey-scans' and you're half way there in figuring out what it really is.
What airports need is private but accountable security paid by airlines, with the Israeli strategy of intelligence directed operations. Do the WTMD, and if you beep it, then you get a second scan in the TeraHertz machine, and if you fail that, get a pat down and failing that a more thorough search in a private video recording room with the help of latex or nitrile gloves and lube
or not flying if you can't get to a film X-Ray facility in time. However that won't be necessary much as properly and thoroughly trained security and interrogation agents as used in Israel & El-Al flights will be able to determine whether you're a true threat or not.
There will be an option to opt-out. Go through the metal detectors. What are they going to do when the million dollar TeraHertz machines aren't functioning? Cancel all flights? 9/11 happened (at the airports point of view) not from a failure of security equipment but new tactics and sloppy complacent staff & procedures.
Short version: It's all just security theatre.