Thomas Jefferson, in ‘Notes on Virginia’, was very clear in his opposition to immigration in large enough numbers to alter the character of American culture and politics at any level. The Know-Nothings stood on firm ground.
Yes. Jefferson also explained why he cut legal corners to purchase Louisiana to create a buffer between the Anglo culture of the Eastern States & the Hispanic culture to the South West. He was not anti-Mexican; but he understood the significant differences, and the consequences of too much “diversity,” in American communities. Our “Politically Correct” politicians, journalists & educators are simply in denial.