When you look at what has happened over the last few decades the natural fluctuations point in the opposite direction of what has actually occurred. When they run the models and plug in the man-made pollution, the correspondence is exact. Beyond that, the scale of natural fluctuations has now been far exceeded by the impact of man-made global warming.

The presidency is more than a popularity contest.

I do genuinely believe that the political system is not linear. When it reaches a tipping point fashioned by a critical mass of opinion, the slow pace of change we're used to will no longer be the norm. I see a lot of signs every day that we're moving closer and closer to that tipping point.

I am a passionate advocate of getting special interest money out of politics.

There are many who still do not believe that global warming is a problem at all. And it's no wonder: because they are the targets of a massive and well-organized campaign of disinformation lavishly funded by polluters who are determined to prevent any action to reduce the greenhouse gas emissions that cause global warming out of a fear that their profits might be affected if they had to stop dumping so much pollution into the atmosphere.

Adopting a central organizing principle means embarking on an all-out effort to use every policy and program, every law and institution, to halt the destruction of the environment.

We're all capable of mistakes, but I do not care to enlighten you on the mistakes we may or may not have made.