That is the difference we make in the world. And our own safety, our own security, depends upon our willingness to do what it takes to defend this nation and uphold the values that we stand for - timeless ideals that will endure long after those who offer only hate and destruction have been vanquished from the Earth.

I will work every single day to make sure that America continues to be the greatest nation on earth.

It was basic research in the photoelectric field-in the photoelectric effect that would one day lead to solar panels. It was basic research in physics that would eventually produce the CAT scan. The calculations of today's GPS satellites are based on the equations that Einstein put to paper more than a century ago.

Our alliances and partnerships are not directed against any nation.

Reverend Wright has been my friend and mentor for over 20 years.

The only resolution is for the aspirations of both sides to be met through two states, where Israelis and Palestinians each live in peace and security. ... Israelis must acknowledge that just as Israel's right to exist cannot be denied, neither can Palestine's. The United States does not accept the legitimacy of continued Israeli settlements.

We need more responsibility, but we need it not just when there's a crisis. I mean, we've had years in which the reigning economic ideology has been what's good for Wall Street, but not what's good for Main Street.