The survival of the United States of America as we know it is at risk. And even more — if more should be required — the future of human civilization is at stake.

Where solar energy is concerned - and wind energy and battery storage and electric vehicles and efficiency technologies - that is what we are now seeing. So, yes, I'm very optimistic, but anyone who works on the climate crisis has an internal struggle between hope and despair. I won't deny that, but hope has always prevailed in my outlook.

Population growth is straining the Earth's resources to the breaking point, and educating girls is the single most important factor in stabilizing that. That, plus helping women gain political and economic power and safeguarding their reproductive rights.

I don't have the illusion that there's any position or role in the world with as much potential for bringing about change as that of president of the United States.

If we walk down the sidewalk of any street in America a significant number of the people we pass by, if we dug into what they're going through in their lives, they're carrying burdens that they don't talk about but they're extremely heavy and painful. And so, one of the secrets of the human condition is that suffering binds people together. And when you go through something agonizing, others who know what you're feeling because they've been through it will so often reach out to you and connect with you, and give you strength and lift you up.

We have a planetary emergency. We have to find a way to create, in the generation of those alive today, a sense of generational mission.

I'm passionate about restoring the efficacy of American democracy, making capitalism sustainable, prioritizing advances in technology, and seizing the opportunities to use that kind of innovation to help usher in a new economy that doesn't rely on carbon-spewing fossil fuels.