World War I was not inevitable, as many historians say. It could have been avoided, and it was a diplomatically botched negotiation.

It's an improvisation on a theme. You know where you want to go, but you don't know how to get there. It's not linear.

As countries grapple with modernization, people who are left behind tend to hold firmer and firmer to their view of the evil of modernity.

Our enemy is Al Qaeda and its allies, people who have publicly said they wish to attack the United States again, people who have publicly called on nuclear physicists and engineers to help them gain access to nuclear weapons, which, as the whole world knows, Pakistan has.

The World War II generation believed the United States could do anything - anything... And Vietnam was a shattering experience for everyone.

A peace deal requires agreements, and you don't make agreements with your friends, you make agreements with your enemies.

Diplomacy is like jazz: endless variations on a theme.

I tell you, he [Milosevic] continued, Izetbegovic has earned Sarajevo by not abandoning it. He's one tough guy. It's his. These words were probably the most astonishing and unexpected of the conference.

In diplomacy, as in life itself, one often learns more from failures than from successes. Triumphs will seem, in retrospect, to be foreordained, a series of brilliant actions and decisions that may in fact have been lucky or inadvertent, whereas failures illuminate paths and pitfalls to be avoided.

A world without the United Nations or with a paralyzed United Nations would be far more costly to all of us and far more dangerous to peace and stability.

The United Nations is an indispensable but deeply flawed organization. It is valuable to the United States, and the United States is invaluable to it. We need to reform it.

Bureaucracies have a natural tendency not to cooperate, coordinate or consolidate with each other. They won't cooperate with each other - unless they are forced to do so by political level authority.

Nothing generates more heat in the government than the question of who is chosen to participate in important meetings.