X-raying airline pilots -- what on Earth is the point of that?

The Pilot’s Union is supporting their members who are objecting to mandatory TSA full-body scans before boarding the aircraft they are going to fly. Pilots are concerned that while the individual dosage of radiation may be small, they may be scanned three or more times per day in their regular work schedule, and the long-term accumulative effects of this exposure are not well researched.

Whether they have reason to fear the X-rays or not, what on Earth is the TSA thinking? If a pilot wants to destroy a plane, he doesn’t need to smuggle explosives on board to do it. He is sitting at the controls. He can fly the plane into the ground, into a mountain, or a tall building. How is scanning the pilot going to add anything to flight safety? Or is it just one more example showing that TSA really stands for Transportation Stupidity Administration?