While the United States has often taken the wrong path, it has rarely failed to demonstrate - at least in the long run - the courage to reverse its steps.

When it comes to climate change, I think that success at home is directly tied to our ability to lead effectively abroad.

Some friends of Israel believe that the Palestinians will never, in their hearts, accept a Jewish state in Palestine. Yet Germans and French, Chinese and Japanese, Mexicans and Americans have overcome their once insurmountable differences. Palestinians and Jews also have much to gain from peaceful coexistence.

By virtually every metric, the liberal international order has made the world healthier, wealthier, wiser, more secure and more tolerant than it has ever been.

I don't think anyone in the 1990s, the late '90s, anticipated that the Putin they knew then would become the Putin we know now.

My father's father fled a pogrom in Russia in the early 20th century and was welcomed to the United States. So was my stepmother, who escaped as a young girl from Communist Hungary in 1950.