His argument is basically it's not worth doing it "Because vast part of 21st century emissions come currently poor world".
That seems like a rather odd stance to me, effectively he is saying it's too expensive for us as a rich country to do and at the same time expects poorer countries to do it - how can they manage that if it's already too much for the richer countries?
That seems like a rather odd stance to me, effectively he is saying it's too expensive for us as a rich country to do and at the same time expects poorer countries to do it - how can they manage that if it's already too much for the richer countries?