[caseysoftware]

Reasonable hypothesis but not correct in the US.

The point where you present your ticket+ID is before and separate from the physical screening. It could be anywhere from a few meters to dozens of meters separating them.

At the screening stage, the agents do not know who you are or your nationality.

[figassis]

It's not about being recognized, it's about when you are asked to be patted down, having the courage to lie "I can't raise my arms over my head", knowing the risk of being caught is at worst not making this flight. For a foreigner it might be getting banned permanently from the country. Same concept as self censorship. You do what you're told and then you go enjoy your vacation.

[caseysoftware]

Understood and reasonable but one correction:

> when you are asked to be patted down, having the courage to lie "I can't raise my arms over my head"

You only get a pat down if you trigger additional screening or opt out. Not being able to raise my arms is NOT opting out. Therefore, no pat down.

[mothballed]

I don't think I've ever made it through the physical screening without betraying my accent at some point. Sure you can work your way out of an accent, but it's not easy, and requires years of practice, and probably the most reliable (but fuzzy) low-scrutiny indicator of someone who "aint from around here" in a multicultural society where looks are ~useless for such determinations.