The United States is now alone in the world in its rejection of the Paris climate agreement. Syria announced it would sign that agreement Tuesday in Bonn, Germany at the United Nations yearly climate change conference. The treaty calls for individual limits on greenhouse gas releases among participating countries. It is not binding nor does it provide any enforcement mechanism. Barack Obama signed the treaty in his second term as U.S. president. However, in June, President Donald Trump withdrew the nation from the agreement. He said the agreement hurts the U.S. economy and American workers.