Yup, 1945-1970 America was 90% White, and that period coincided with what is known as "the Great Compression". Economic policies in the wake of the New Deal established a regime of rising single-earner wages, declining inequality, increasing happiness, and a decreasing income and wealth gap between the ownership class and the labor class.
1970 was the inflection point when all that began to unravel, and then accelerate under Reaganism.
