USA and China combined accounts for 42% of CO2 emissions of the world. Per capita, USA is still the largest emitter. Sector-wise, electricity and heating still accounts for 41% of total emissions, whereas transport accounts for 23% of total emissions. So changing the mindset of USA and China won't be enough and any easy. But the change in generation of electricity, conservation of heat within buildings and better access & more use of public transport can solve many problems.