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.
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.
I know that I'm not the easiest person to live with. The challenge I put on myself is so great that the person I live with feels himself challenged. I bring a lot to bear, and I don't know how not to.
We will build our defenses beyond challenge, lest weakness invite challenge. We will confront weapons of mass destruction, so that a new century is spared new horrors.