Number Needed to Treat

So in the medical world, we think about the efficacy of an intervention by calculating how many people need to be treated for one additional beneficial outcome to occur (as opposed to doing nothing or whatever is the current standard treatment). Anyway, an NNT of 10 to 20 is usually considered really good. NNTs of less than 200 are generally considered worthwhile interventions assuming risks are low. In the case of terrorism, the NNT seems to be about 500 million or so. May I suggest that the same people who think these ridiculous airport security procedures are anything but theater also probably think homeopathic medicine is effective.