There's a name for it: Security Theater [1]. "Security theater is the practice of taking security measures that are intended to provide the feeling of improved security while doing little or nothing to achieve it."

Some have likened it to a jobs program that both increases the surveillance capability of the government as well as provides political creds for the representatives in those districts where airports exist, similar to the Military Industrial Complex.

[1] https://en.wikipedia.org/wiki/Security_theater