Nobody's interests are served by what's happening in Syria today. It's a catastrophe. It's the worst human catastrophe since World War II. And, as I said just now, it represents a failure of the entire international community to come to grips with solving it.

I'm going to be a president who believes in science.

America is the most powerful economy in the world. We're an $18-trillion-dollar economy.

America has everything most countries envy. A Constitution which is the treasure of mankind, a strong military, natural resources of every kind. Above all, as Tocqueville said, a good people, which is what makes us great.

America has an ability to try to make some things happen that other countries don't necessarily have.

Those who deny the science or choose excuses over action are playing with fire.

In this remarkable time for the world, I refuse to believe it's time to stop believing in the possibilities of our remarkable country. I refuse to accept the downsizing of the American Dream. I refuse to bet against American entrepreneurial spirit and American ingenuity.The competition's tough, and it requires us to be tougher - tough-minded, never hard hearted.