What I remember thinking at that point, having gone through both the ups and downs of my first four years, and seeing the sea of people was, "What a remarkable country this is and how lucky am I that we live in a place where the son of a single mom, not born into any kind of fame or fortune, in a pretty remote state somehow can end up be in a position to - to make a difference."

We can lose so much of what we've gained in terms of the kind of democratic freedoms and market-based economies and prosperity that we've come to take for granted.

Without regard to whether some place is wealthy or poor, everybody should have the chance at clean air and clean water.

We must educate our children to become like young Egyptian people.

We're not going to have you burdening the health system.

When we helped prevent the massacre of civilians trapped on a distant mountain, here's what one of them said: "We owe our American friends our lives. Our children will always remember that there was someone who felt our struggle and made a long journey to protect innocent people." That is the difference we make in the world.

I believe that the best measure of whether a nation is going to be successful is whether they are tapping the talents of their women.