Climate change is the greatest threat of our time.

I think that one of our most difficult international challenges is clearly climate change and making sure that the Paris agreement goes forward. While I think the international community understands that President Trump is not taking the same position as President Obama.

Critics play a dangerous game when they denounce the science and law EPA has used to defend clean air for more than 40 years. The American people know better.

Climate change is the greatest threat of our time.

I think climate change is probably the most extreme, and it's been going on for years because it's very difficult to talk about a planetary issue like climate change and to get people who live within four-year electoral cycles to actually pay attention to something that you predict is happening way in the future.

But just [proposing the standard] puts companies on notice that if you're looking to construct a new natural-gas or coal facility, you really need to pay attention to these. This is what they should be designing new facilities toward as soon as this proposal hits the streets.

But I will tell you that I didn't go to Washington to sit around and wait for Congressional action. Never done that before, and don't plan to in the future.