Correct. And it protects everyone from “unreasonable “ searches. The SCOTUS has determined that searching foreigners at airports is not unreasonable.

Which has told me as a European that the US is an unreasonable place I don't want to enter anymore, neither for business nor leisure.

But I have full understanding for people who are in a situation that the US is still the smaller evil.

They have also said it’s not unreasonable to detain and in some more narrow situations search American at the border.

Do most EU nations have constitutional protections as strong as the US bill or rights?

It depends what you mean. In the UK our institutions are centuries old. Heck the working class house my grandmother lived in until she died was older than the state of California.

The constitution is only as strong as the institutions that defend it. The U.S. is not there yet but the political nature of the courts and the judiciary are an anathema to a Brit.

I saw that case. But the TSA agents are like ok otherwise we send you home. I'm happy to make a case but I think it's unlikely to be worth the stress and money