In general, law is a system used by national entities (I'll go with that term in place of a more loaded one like "countries" or "states") to keep their people in check and maintain prosperity for the many in terms of intra-entity interactions. More recently, treaties such as the Vienna Convention on Diplomatic Relations function as a means of keeping order and prosperity in terms of inter-entity interactions.
When people or nations commit acts that harm the many, the appropriate body, whether the presiding national entity or the community of national entities, respectively, responds with punishment typically as deterrent to further such acts. And so the system more or less functions to keep everyone happy, except when it doesn't. Every now and then, some group or another commits genocide or eugenics or forces labor upon its citizens and inevitably, a number of people suffer, and the regime eventually ends.
Then there's the International Criminal Court at the Hague. Arguably one of the greatest achievements of inter-entity cooperation in history, functioning to try those who'd fall outside the scope of any one entity, or across the scopes of too many for any one to have presiding jurisdiction. Perfect for trying genocidal tyrants, mass murderers, or perhaps a few Nazis whose war crimes were committed seventy years ago. But what's the point?
Nearly every German, for instance, is raised with a very real understanding of the significance of their history, and the opinion that it was wrong. It seems a little vengeful to target 90-year-old Nazis for crimes they realize is wrong, or even for crimes they are proud of, and there doesn't seem to be much of a benefit with regards to preventing it from happening again?
It would seem to me that in many if not most cases, the International Criminal Court is a powerful tool for beating a dead horse, even if the historical significance behind it isn't.
Does the International Criminal Court at the Hague serve a quantifiable purpose beyond taking a last stab at punishing those long past their crimes?