[muawiyah]

Wouldn't be a new law ~ just an administrative determination based on law current when they were born. Simply require them to be added to the family's visa when they "visited" the US.

This goes on all the time.

Administrative error may be corrected without respect to the ex post facto law prohibition.

Think of it like the title to your home. You get insurance just in case someone made an administrative error a couple of centuries ago.

[El Conservador]

An administrative determination, such as an executive order, would be challenged in a lower court, and overturned.

The only way to strip citizenship away would be to amend the Constitution to clarify the language in the 14th Amendment.

Even so, it couldn’t be applied retroactively, in keeping with the prohibition of ex post facto laws.