My understanding was that until they can make sure it cannot be weaponized against the US, only US citizens will be allowed to use it.

(Read: the US lacks authority to ban use by citizens and doesn't want to risk their hand in court, particularly since lawyers who know anything have all left US government and what remains are complete incompetent jokes who can't even win slam-dunk cases due to repeated procedural errors. The nice thing about blocking non-citizens is they are easy to bounce out of court on standing)