Immigration keeps this country young, it keeps it dynamic, we have entrepreneurs and strivers who come here and are willing to take risks, and that's part of the reason why America historically has been successful.

There is no doubt that the actions of ISIS are designed to amplify their power and the threat that they pose. That helps them recruit. That adds in the twisted thoughts of some young person that they might want to have carry out an action that somehow they're part of a larger movement.

For decades, we've been told that it doesn't make economic sense to switch to renewable energy. Today, that's no longer true.

I've said many times around the world that like any government, like any country, like, any set of human institutions, we have our flaws. We've operated imperfectly. There are times we've made mistakes.

A change is brought about because ordinary people do extraordinary things.

Look at Chancellor [Angela] Merkel, her personal story helps to tell a story of incredible achievement that the German people have embarked on and I think is something that you should be very proud of.

I spoke on the phone with President Rouhani of the Islamic Republic of Iran. The two of us discussed our ongoing efforts to reach an agreement over Iran's nuclear program. While there will surely be important obstacles to moving forward and success is by no means guaranteed, I believe we can reach a comprehensive solution.