Does the US have an specific guarantee that we will ignore religion on foreign visitors & immigrants

I know the rules of entry are pretty complicated, and therefore there is no general guarantee of fairness or impartiality. People can be blocked from entering for lots of reasons. Could one of those reasons be religion? Can we stop Wiccans or Obediah or Moonies or Satanists or Islamics from entering just based on requesting that disclosure on the application?

I would imagine that Constitutional protection would not apply to people who aren’t yet in the country, so yeah. Personally I think we should exclude Lutherans just because they are the only religion no one seems to hate.

That does not seem to me toi be limited to inside the territory of the United States. It would only be limited to what Congress (and by extension the US Government) can deal with. So if the Congress legislated to forbid US citizens from making the pilgrimage to Mecca, that would be unconstitutional, even though it deals with what people do outside the country.

In addition, the protection is not limited to US citizens: a law requiring non-citizens present in the US to go to church on Sunday would be unconstitutional too.

The government can stop people from going to Cuba, Libya, Congo, Viet Nam, or Vatican City. It can certainly stop all contact with Arabia, and thus Mecca, like we did with Iraq and Iran.

It’s all about how you write the law. If you block folks from visiting Arabia, it has to be written with no reference to “for pilgrimage, or worship.” Even then, I’d expect that an argument could be made in court that any blocking, by the US govt, of a citizen’s travel, where the reason for the travel is religious in nature, would be unconstitutional, while still dissallowing other citizens to be blocked. Or something lawyerly, which I’m clearly not.