I've a post up at Demography Matters that speculates on a possible if secondary reason for the North's hostility towards South Korea. North Korea's leadership is so concerned with ethnic purity that it's policy for its security guard to kick North Korean women pregnant by Chinese fathers into miscarriages; South Korea's government, in contrast, is actively encouraging the integration of immigrants and children born to foreign-born mothers into an increasingly cosmopolitan population. Might the North be unhappy with this?
Go, read.
Go, read.