I think what happened with 9/11 is that people sort of felt that it came from nowhere. Whereas I think now we understand the roots are very deep. I say it's like revolutionary Communism, something that is going to have to be knocked out over a very long period of time. This strain of extremism continues to be very strong, whether it's in Afghanistan, or Somalia or Yemen, or any of these places.

If we take all this actions and if it turns out not be true, we have reduced pollution and have better ways to live, the downside is very small. The other way around, and we don’t act, and it turns out to be true, then we have betrayed future generations and we don’t have the right to do that.

If we are going to carry on growing, and we will, because no country is going to forfeit its right to economic growth, we have to find a way of doing it sustainably.

It's not that tens of millions of people all want to be violent. But they share the worldview that then, at its extreme, gives rise to the violence. And in my view, this is why this is such a global problem.

The emphasis placed by more and more companies on corporate social responsibility, symbolises the recognition that prosperity is best achieved in an inclusive society.

I'm afraid that's in the nature of modern politics - it's as much conducted by abuse as argument.

We know the problems, and we know the solution: sustainable development. The issue is the political will.