There are interests which transcend state boundaries: environmental pollution, fisheries management, maritime law, response to large-scale disasters, war crimes

There are interests which transcend state boundaries: environmental pollution, fisheries management, maritime law, response to large-scale disasters, war crimes, slavery, human trafficking, resettlement of refugees, weapons of mass destruction, pandemic disease, ... There already exist a variety of international organizations to tackle these in various ways, established by international treaties... This does not by any means replace national government.