That’s my point. I’ve worked with 2 Chinese nationals in my career (and some of it was pretty advanced stuff). In one case, the guy wrote the code to a flight control system, based on everything he learned here from us...got sent back to China, and took the code, and everything related to it with him - we didn’t even have anything we could use in our project. We just looked at each other and figured out that we were scammed by this bunch.
In another instance we had another Chinese national working with us - got what he needed...but to this day, we don’t know whether or if he sent what he learned back home...but yea, why wouldn’t he? But in his defense, I guess, he was a very nice person (except to my immigrant wife, who could smell a mole 1000 miles away).
The bottom line is that it is MUCH MORE expensive and risky for this country to use people of questionable loyalty, than to use Americans - but US companies simply don’t give a shit regarding that.
Have seen all of that & heard similar stories many times more!
We should not be educating foreign nationals within our country. Let them find their own way, it does not serve us at all as a nation.