The best simpleminded test of expertise in a particular area is an ability to win money in a series of bets on future occurrences in that area.

When a rapidly rising power rivals an established ruling power, trouble ensues. In 11 of 15 cases in which this has occurred in the past 500 years, the result was war. The great Greek historian Thucydides identified these structural stresses as the primary cause of the war between Athens and Sparta in ancient Greece. In his oft-quoted insight, "It was the rise of Athens and the fear that this inspired in Sparta that made war inevitable."

And I hope that we can learn the lessons of the past in looking at the current challenge that China poses to a ruling America.

There are two great tragedies in life: one is to fail to achieve one's grandest ambitions, and the other one is to succeed.

Putin needs to understand and feel in his gut that if the Chechens get a nuclear bomb, they're going to Moscow first, they're not coming to New York.

If the Britain and France had done what they were obliged to do under the treaty and sent troops to enforce the treaty when Hitler remilitarized the Rhineland, the German general staff would have turned Hitler out. And one would not have had a cause for war, and you wouldn't have had World War II.

For interests that are vital to the U.S. - that is, essential for our survival and wellbeing - the U.S. should be prepared to use military force - including unilaterally, if necessary.