We've seen the bankruptcy of many newspapers. We've seen a further erosion of the line between news and entertainment. But I do believe that there is reason to hope that over time we will see the higher-quality journalism rise to the surface.

We know that he has stored secret supplies of biological and chemical weapons throughout his country.

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.

When our founders created America, it was in the age of the printing press, when individuals could freely join the conversation. And that robust, democratic dialogue more often than not lifted up the best available evidence and asserted what was more likely to be true than not.

We ought to approach this challenge [of global warming] with a sense of profound joy and gratitude: that we are the generation about which, a thousand years from now, philharmonic orchestras and poets and singers will celebrate by saying, they were the ones that found it within themselves to solve this crisis and lay the basis for a bright and optimistic human future.

I have faith in the United States and our ability to make good decisions based on the facts.

Today we're dumping 70 million tons of global-warming pollution into the environment, and tomorrow we will dump more, and there is no effective worldwide response. Until we start sharply reducing global-warming pollution, I will feel that I have failed.