The very first immigration law passed by Congress in the US, and passed under the US Constitution, specified that candidates for citizenship must be Whites of good character, so it's clearly not unconstitutional. That law stood for a very long time, and was never found unconstitutional.
I will take your word for this, but this in and of itself does not state or clarify "intent" on the part of the Founders for white immigration only.. The fact that it never was declared unconstitutional may merely be due to the fact that it was not challenged and adjudicated in that regard. The fact that it stood for a long time does not seem to bear on this discussion. Is it not the case that many longstanding laws eventually were taken off the books or supplanted by laws that stated something different.
The Constitution provides latitude for application of wisdom and good judgment in its implementation - law regarding women's right to vote and the civil rights legislation are examples of new rules that supplanted those which stood for a long time or whose applications later were determined to be unwise, unfair, etc. I absolutely make no case regarding any preferred skin color of immigrants, but am concerned about misconstrued, intents, laws and history.
