Rights of free speech are essentially a covenant between a government and its own citizens. A government is not required to extend the same rights of expression to foreign visitors as it extends to its own populace. US law requires that American Nazis be allowed to speak their minds, but it does not require that Norwegian Nazis be allowed into the country so they may do so.

Personally, I would prefer that my government allow anyone from anyplace free entry to say whatever he pleases, but that's just me speaking, not the law.