Suppose as you hypothesize the TSA really doesn't know whether or not they work and whether or not they pose radiation risks to travelers and TSA employees. But they've told the President and Congress that this is the only way to keep us safe and we absolutely must spend $2.4B.
I was proposing two hypotheses. First, TSA knows exactly what is going on and they are lying about it. Second, TSA's testing procedure is flawed so they don't know what is going on, but they may think that they do. So if they are using a flawed test without being aware of the flaws, 'stupid'. If they are using a flawed test and they know it, 'lying'.
Would you consider that 'lying' or 'stupid'?