Founders

These are the first immigration laws passed. And the http://altright.com  article has numerous writings from the Founders on race to show they'd have no egalitarian qualms with that law

Specific Founding Fathers had a stricter idea of race, but it didnt impact the legal tradition. Ben Franklin saying Germans werent white didnt prevent their immigration. Collectively, they were basically white nationalists today in their idea of race.

Also, past devolutions of American identity dont justify all subsequent ones. Currently. white nationalists are the closest to Founder's Intent

https://altright.com/2016/07/26/what-the-founders-really-thought-about-race/

you asked about the Founder's views. It not being in the Constitution explicitly ('for ourselves and our posterity is pretty explicit' imo) is rather meaningless. They expressed the nation was for whites, laws reflected that. Their lifestyles also reflected racist attitudes