"It was huge mistake to avoid working with the rest of the world because (a) we're the largest source of the problem: 4% of us who are in the U.S. produce 25% of the world's carbon dioxide."

Next Quote

There is a point of no return after which warming becomes unstoppable - and we are probably going to sail right through it. It is the point at which anthropogenic (human-caused) warming triggers huge releases of carbon dioxide from warming oceans, or similar releases of both carbon dioxide and methane from melting permafrost, or both. Most climate scientists think that point lies not far beyond 2 degrees C hotter (3.6 degrees F).

— Gwynne Dyer