Five months into his administration, President Trump announced, as promised, that he was notifying the United Nations climate secretariat of U.S. intention to leave the Paris Agreement on climate change.

The agreement is the successor to the 1997 Kyoto Protocol, a predictably failed attempt to commit the developed world to various targets and timetables reducing emissions of carbon dioxide caused by economic activity (which is why it failed). All agreed that Kyoto was a treaty, and all agreed that it could never gain the two-thirds vote required by Article II of the Constitution for ratification, giving it the force of law.