Have North Korea be the prime power in the Korean Peninsula while South Korea is simply playing second fiddle, responding to their actions rather than vice versa*. Bonus points if they are a primary power in the entire Sea of Japan. Even more if NK is a democracy while SK is a despotic Hermit Kingdom.
*I know you could say that SK is simply responding to NK now but thats a discussion for another thread.
*I know you could say that SK is simply responding to NK now but thats a discussion for another thread.