Book excerpt: America's status as a world power lies at a historic turning point. The strategies employed to win the wars of the twentieth century are no longer working, and the United States must contend with the changing nature of power in a globalized world. In America and the World two of the most respected figures in American foreign policy, Zbigniew Brzezinski and Brent Scowcroft, dissect the challenges facing the U.S. today: whether we should withdraw our troops from Iraq or keep them there; how we should approach Iran, Israel, and Palestine; how aggressively we should push to expand NATO to Russian borders; how we can (and must) maintain our role in the Far East; and many other questions. In spontaneous and unscripted conversations the two authors explore their agreements and their disagreements. An essential primer on a host of urgent issues, America and the World defines the center of responsible opinion on American foreign policy at a time when the nation's decisions could determine how long it remains a superpower