There are 195 nations in the world. They have just concluded two weeks of meetings in Bonn, Germany to carry forward the Paris climate change agreement. This year two holdouts, Nicaragua and Syria, joined the Paris agreement.
One nation, only one, the United States, announced it would withdraw although the technicalities of the agreement postpone finality of the withdrawal until 2020 (if we get to 2020).
Peeling the Onion 