Why is South Korea so Nice to their Aggressive Neighbor?
Because they fear victory, and for good reason. This is a great background article, as it explains that South Korea knows that the North will eventually fall, so the biggest concern is one of timing. It explains how the economic consequences of immediate reunification would be disastrous for South Korea, causing them to tolerate the aggression of the North while providing aid, in hopes that North Korea’s economy will be somewhat reformed by the time that it is absorbed by the South.