The world cannot count on them all to do it on their own. China, in particular, looks likely to fail to deliver on the fairly weak pledges it made in Paris. Fortunately, there is a stick available to encourage ambitions to decarbonize: a tariff based on the carbon embedded in the imports into the United States, the European Union and other rich countries.
they are also reforesting at record speeds, redoing their infrastructure to be less car dependant, etc. its the very last country in line to be critical about when it comes to this.