Pat Buchanan spelled it out in his book “Death of the West”.
https://smile.amazon.com/Death-West-Populations-Immigrant-Civilization/dp/0312302592/ref=sr_1_1?ie=UTF8&qid=1515430538&sr=8-1&keywords=death+of+the+west+patrick+buchanan
I'm a big fan of Buchannan's speech at the 1992 GOP convention in Houston:
Buchanan 92 Culture War Speech Still Provokes