South and North Korea get nasty again

The last South Korean President worked towards peace with North Korea. A new train link was set up and an industrial estate was built by the south on the Northern side. The new conservative South Korean President has said he will be less tolerant towards North Korea and has shown it. Now in responce North Korea has sent away some of the South Korean managers. It's hard to think of how diplomacy should be balanced. Do you let North Korea get away with things in the hope of peace? Or do you question and stand up against North Korea and threaten peace?