One of the most important things in politics is you've got to keep your mind infinitely curious and alive to what is happening differently.

We need to develop the new green industrial revolution that develops the new technologies that can confront and overcome the challenge of climate change; and that above all can show us not that we can avoid changing our behaviour but we can change it in a way that is environmentally sustainable.

Do I know I'm right? Judgements aren't the same as facts. Instinct is not science. I'm like any other human being as fallible and as capable of being wrong. I only know what I believe.

I just want to say this. I want to say it gently but I want to say it firmly: There is a tendency for the world to say to America, ‘the big problems of the world are yours, you go and sort them out,’ and then to worry when America wants to sort them out.

September 11 was, and remains, above all an immense human tragedy. But September 11 also posed a momentous and deliberate challenge not just to America but to the world at large. The target of the terrorists was not only New York and Washington but the very values of freedom, tolerance and decency which underpin our way of life.

The art of leadership is saying no, not saying yes. It is very easy to say yes.

They could have been removed. They could have been hidden. They could have been destroyed.