The U.S. cannot go it alone simply when it is convenient.

There is not an inherent contradiction between a Ukraine that has longstanding historic and cultural ties to Russia, and a modern Ukraine that wants to integrate more closely with Europe.

President Obama is perhaps the smartest person I've ever worked with.

I am very aware of being black and female because that's what I am.

I have to separate my personal concerns from my professional responsibilities.

If you're trying to get something done, there will always be people who don't want to see you get something done, or who have a stake in the status quo. And if they approach that through ad hominem criticism of you, you've got to have enough confidence and thickness of skin to be able to endure.

It may not be what you would've chosen, but we all have a responsibility to be active citizens and shape our system and our future.