As a matter of fact, it's in our interests that we help reformers across the Middle East achieve their objectives. This is the fundamental challenge of the 21st century.
Today I challenge our nation to commit to producing 100 percent of our electricity from renewable energy and truly clean carbon-free sources within 10 years.
So long as I'm the president, we will. I clearly see the challenge. I see the challenge of what these threats pose to our homeland, and I see the challenge of what these threats pose to the world.
Writing is something that you can never do as well as it can be done. It is a perpetual challenge and it is more difficult than anything else that I have ever done.
It is impossible to remain indifferent to Japanese culture. It is a different civilisation where all you have learnt must be forgotten. It is a great intellectual challenge and a gorgeous sensual experience.
One of the things I learned as president is that your life is just not going to unfold the way you want it to. There will be surprises, challenges, and therefore the question is how you deal with the unexpected.
I remember, right after Hezbollah launched its rocket attacks on Israel, I said: This is a clarifying moment; this is a chance for the world to see the threats of the 21st century, the challenge we face.
I always want to set myself a challenge by doing something no-one would expect me to do! But, having said that, I don't feel as a musician you can steer too far away from what you normally do.