How we cite our quotes: (Section)
Quote #4
That this act shall not apply to diplomatic and other officers of the Chinese Government traveling upon the business of that government, whose credentials shall be taken as equivalent to the certificate in this act mentioned, and shall exempt them and their body and household servants from the provisions of this act as to other Chinese persons. (Sec.13)
Any time you're explicitly dealing with another government, you're specifically engaging with foreignness. China had its own laws. In order to enact this specific law, the U.S. government had to negotiate an entirely new treaty.
Quote #5
That hereafter no State court or court of the United States shall admit Chinese to citizenship; and all laws in conflict with this act are hereby repealed. (Sec.14)
Forbidding Chinese immigrants from being citizens automatically keeps them as foreigners. They can never naturalize and be thought of as America. It's the literal enforcement of the Other.