As we collectively hurtle into the era of climate change, international relations as we’ve known them for almost four centuries will change beyond recognition.

This shift is probably inevitable, and possibly even necessary. But it will also cause new conflicts, and therefore war and suffering.

Since the Peace of Westphalia in 1648, diplomats have — in peacetime and war alike — for the most part subscribed to the principle of national sovereignty. This is the idea, enshrined in the Charter of the United Nations, that foreign countries have no right "to intervene in matters which are essentially within the domestic jurisdiction of any state.”