Oh, they're quite great at singling out disabled people, women who have the audacity to bleed into a pad rather than an internal "sanitary product", and anyone else with a non-TSA-approved body, which seems to change on a daily basis but let's just say it definitely reflects the mindset of the people the TSA hires.

So, yes, they have a use. They keep people like me off planes, since the TSA has no policy other than "do whatever the hell we want to you, and we don't care about your dignity, keeping your carry-on baggage from getting stolen, or actual security." Security theatre costs money to the taxpayer and the airlines, it hurts whomever the TSA decides should be harassed (and oftentimes these are people who have specifically enumerated legal rights, but it's not like the TSA cares...and even people who don't have such rights deserve dignity and to be able to fly), and it lends itself to people thinking they're safe when they're not. Costs, hurts, lies. That's what the TSA is all about.