claim: I think about all the 194 countries that signed onto the Paris accord, the U.S. is the one that's leading the world in reducing emissions.
evidence: 187 states and the EU, representing more than 87% of global greenhouse gas emissions, have ratified or acceded to the Agreement, including China, the United States and India, the countries with three of the four largest greenhouse gas emissions of the UNFCCC members total ( about 42% together ).