There is a huge difference between a foreign national and a naturalized citizen. Proceeding in a conversation on this topic without using these terms correctly will only lead to confusion.
> You're assuming bad faith.
On the contrary, I misinterpreted your meaning precisely because I was being charitable.
Your original post could've been interpreted in two ways:
1. Charitably: you simply didn't know that these people were citizens of the USA, and are reasonably suspicious of someone who built their career and fortune here but who doesn't want to obtain citizenship.
2. Uncharitably: you distrust people because of where they were born.
I chose the charitable interpretation.