If we needed a reminder about the consequences of appeasement, today's latest act of war by North Korea is a good example. When you tolerate numerous acts of hostilities by a rogue state, including allowing it to get away with sinking one of your warships without significant consequence, don't be surprised when its leadership feels confident in firing artillery into your country. At least this time South Korea struck back with its own guns, albeit in a fairly minor way.
For years, U.S. and South Korean policy toward the North has been essentially one of appeasement and wishful thinking. At the same time, both have supported limited economic sanctions, which while doing nothing to negate the North Korean military threat, created even more hostility. Now the threat has increased and is backed by an unknown number of nuclear weapons. Time and time again North Korea has been allowed to get away with hostile acts, to the point where it has to believe it can do pretty much whatever it wants, and that the South and its U.S. ally are too afraid of war to respond with anything more than empty talk and economic sanctions. Its belligerence has paid off before, forcing negotiations and even agreements which brought direct aid to North Korea.
Although appeasement can delay war, it tends to breed more aggression, confirming the aggressor's views of its enemies as weak and irresolute. But at some point the aggressor is going to miscalculate and go too far, and there will be a war. Hopefully it won't happen now, but it's only a matter of time unless there is a drastic change in policy toward North Korea.