What is to prove? Where are foreign powers or corporations listed as protected in the constitution?

Read it, it’s a short read.

You’re the one making bizarre statements unsupported by any cogent arguments.

Historically, unregistered foreign agents get deported, imprisoned, or executed. Not protected.

There is a long, long history of this. It’s only recently where it was possible to do this with any meaningful effect without physically being present in the US, which is the reason it is a lot harder to prosecute now. But the laws are still on the books, and the Supreme Court has had no issues supporting them in the past.