Korea being thorn into ever since does not seem to be a great example, but that's not really the issue. First, we might want to define "success". Does this word means that the people should start to live and think as westerners do or that they could leave the way that suits best the majority of them ?

Once success defined, we could then asses its rate: 50% and around means sheer luck. Only if over, say, 75% would seriously suggest that the action was worth it. I'm afraid we're very, very far from it.