Good quote, but it's fake.

A congressman saw this in a letter to the editor in the Washington Star in 1957 and had it read into the Congressional record as proof of a communist plot. That prompted the paper to research it, and they determined that the book did not exist and traced the quote back to Eustace Mullins.

I don't doubt that leveraging racial tensions was the Soviet strategy to destabilize the United States, but this quote and the book it supposedly came from are fake.