So many have noted how the TSA is security theater, and even explained why it’s so bad, but I want to offer some reasoning as to why it’s still worth it. In a nutshell, it makes passengers feel safer. We all know that TSA is mostly useless at actually stopping a motivated threat. It’s really only good for stopping poorly planned or spontaneous threats which are generally uncommon in air transit. But for the general masses, that intrusive security screening feels thorough and so people assume their flights are safe and continue to fly all over the country. This keeps airlines in business, taxes going to localities and states from their airports, and creates a ton of jobs from gate agents to coffee shop clerks to rental car agents and beyond. The minute people stop thinking air travel is generally safe and secure is when all of that collapses. So we pour money into theater to make things look and feel secure (though most of the effort to actually secure things is behind the scenes, DHS/FBI/CBP/etc. using threat intel to stop planned attacks long before TSA would ever need to interact with anyone).

To your second question, we don’t really know if it scares away threat actors, but it likely does to some extent. It preps passengers to be somewhat more alert that they are in a secured area past the checkpoints, and complicates planning attacks at a minimum. No security system is 100% effective, especially one that needs to work at scales like TSA does, but the theater isn’t really an accident and for sure TSA heads know that’s all it really is, and they are fine with that.

Lastly, it’s not just the US with screenings like this, flying through Heathrow in the UK was just as bad in every way.