Chances are, the conversation wouldn't happen like that
Mainly because the USA has signed treaties that make it illegal to refuse entry to a citizen.
That, and when you make a self-report of risk be a metric for spreading the risk, you increase the risk and the amount of lying. But you don't help anyone. So your plan fails for many reasons.
Wait a minute. The USA ignores treaties left and right and constantly bombs and invades countries because they want to leave the US-dollar as reserve currency. They torture and hold people without trial. They pay millions to destabilize Syria, Ukraine and dozens of other countries.
But they can't refuse entry because of some treaty with Libera?
Since when did the USA care about any treaty?