What Would It Take For The Paris Climate Summit To Succeed?

There’s a lot of focus now on the politics of Paris. Will poor countries get the "climate aid" they want? Will China agree to reduce its growth, leaving millions more in poverty, by committing to far-reaching carbon cuts? What will be the wording of the treaty that emerges?

It’s easy to become cynical. Let’s instead take a step back and ask a much more interesting question: what would it take for Paris to succeed? By this, I don’t mean that the delegates manage to sign some kind of treaty. I mean, what would it take for Paris to have a real impact on climate change?