So, usually in a representative democracy (republic or not), the judiciary power is supposed to check and limit the other two (to avoid a tyranny of the majority). You can have that done in two way: with "case law", the only way in some countries (like the UK): basically if a law is enforced against a minority, it will be enforced against the majority. Other countries added a consitution. Its use is to limit the executive and legislative power of the government: the legislative power is supposed to prevent the law/executive order from existing or being executed, and base that decision on the constitution.

TL:DR: no, it doesn't even apply to US citizen, only to US government.

PS: "tyranny of the majority" for some is a definition fascism, i disagree, to me it isn't even proto-fascism, it lack a weird mythos about internal enemies and a few other mythos. It's closer bonapartism, or cesarism at worst. To be clear i think it is a precondition to have fascism (I.E as long as your case law/consitution is enforced for everybody the same way, you aren't a fascist state).