Japanese have no say in CO2 emissions by any other country, including ones relying on coal plants. Yet they suffer from the externalities of it.
Tragedy of commons. WWI -> League of Nations, WWII -> UN ... How about establishing a world government without WWIII this time. Though what the frak i'm talking about if we can't even stop a government from butchering tens of thousands of their own people (like Sudan, Siria)