Because totalitarianism goes down smoother with junk science-based policy?
The FT comments:
… playing a constructive role would alter at a stroke the world’s perception of a prickly rising power unwilling to contribute to a global system of rules. China’s dominance would be accepted less grudgingly if it exercised power with commensurate responsibility. It would gain influence in global standard-setting, whether in carbon reduction or other areas. Therein lies Beijing’s true prize.