No challenge poses a greater threat to future generations than climate change.

Clearly, the international warning system for disease outbreaks failed the people of Liberia, Sierra Leone, and Guinea.

I have been concerned that, while we have stemmed the tide, some may think that the outbreak is over.

I am also very concerned about any new funding for the Palestinian Authority, given President Abbas's unilateral actions.

You have said repeatedly that no deal is better than a bad deal.

Do you really see any evidence that the regime is seriously interested in giving up its nuclear program and working with the international community?

We somehow have failed here, and I would be interested in having a serious discussion.

The overall package must ensure we have closed all pathways to a bomb.

I hope you will assure the members of this committee that any final deal will verifiably close all possible pathways to a bomb.

Can you assure us that a good deal includes the following: dismantling Iran's centrifuge infrastructure...

I don't understand why we can't communicate more effectively.