"The rise of the presidency began with the Louisiana Purchase, which in 1803 doubled the land mass of the United States. History taught the framers that, just as Rome changed from republic to empire with conquest of new lands, territorial acquisition would lead to the centralization of political power."

"Cyber attacks are not what makes the cool war 'cool.' As a strategic matter, they do not differ fundamentally from older tools of espionage and sabotage."

"An empire that extends itself selectively is just being prudent about its own limitations. A republic that supports democratization selectively is another matter."

"Marriage is the most obvious public practice about which information is readily available. When combined with the traditional Jewish concern for continuity and self-preservation - itself only intensified by the memory of the Holocaust - marriage becomes the sine qua non of social membership in the modern Orthodox community."

"There are books of which the backs and covers are by far the best parts."

"I live with one foot in the sand and one in the snow. There's European egocentricity, and the African opposite. I normally say that my African experience has made me a better European."

"If you saw Queen Elizabeth it would be amazing, she came from another planet. She was so attractive in what she was wearing."

"You're working on being a father, so that is something that when you experience it you'll understand the profundity of wanting to protect something dear to you."