Full body scans, regardless of their intent, are entirely personal.
My first instinct is that I don't think people should be made to go through them. A coworker was recently informed that her child would not be going through the scanner and would have a pat-down instead. Her question was, obviously, who the hell is going to be patting down my child?! I don't know this person - and because they are in uniform I should trust them entirely? We all know that doesn't always end well.
Good luck explaining to your young kid that all of those times you told them not to let a stranger touch them don't count when you are in an airport...in fact, don't tell them that...that sounds bad. Explaining to them that they will have to carry around a never-ending supply of insect reppeallant when the Spider Apocolyps occurs might go over better.
Anyway my second instinct is: think of the society we live in. Women and men ...and far too often teenage girls, are constantly being looked at for their bodies. Judeged, ridiculed, considered objects (yes, this does happen to men also albeit for the most part far less often). Why is it that people are "fighting the fight" over their own security but NOT over their own sanity? (don't get me started on the problem with making people feel unsafe everywhere they go...as if what we get on the news weren't enough now we have to be told everytime we walk uncomfortably through an airport).
I am reluctant to say that if we are accepting one negative thing we should accept the lesser evils as well...just food for thought.
Anyway I like travelling too much to argue over it...do what you will!