This feels like a hypothesis with null testing of N=1 (China, North and South - which is a bit like saying "North Americans, Canadians and Mexicans). A big MAY

This feels like a hypothesis with null testing of N=1 (China, North and South - which is a bit like saying "North Americans, Canadians and Mexicans). A big MAYBE behind of lot of words and reasoning. IME that usually leads to good sales for pop non-fiction, but not a meaningful cause&effect relationship, necessarily.