You could be in the United Nations office all night every night and still feel like you were not making a sufficient dent in the world's problems. I think the key is prioritization. But every job presents the tyranny of the inbox, of allowing the urgent to crowd out the important. So we have to have our lodestars.

Re-examining our reasoning is not something that has come naturally to American statesmen.

I'm going to Washington on a fateful, even historic, mission. I feel that I am an emissary of all Israel's citizens, even those who do not agree with me, and of the entire Jewish people

I think we do have an interest in combating states that try to cross borders and steal parts of other people's country.

There's something beautiful about working in the one place in the world where the world is present, like United Nations. Otherwise, one would have to go to each of these countries to negotiate.

When it came to the Vietnam War, Mr. McNamara was an early advocate of escalation but came to realize the flaws in the American approach earlier than many of his colleagues. Yet in public, he continued to defend the war.

My basic feeling about military intervention is that it should be a last resort, undertaken only to stave off large-scale bloodshed.