Hill and Wang. 320 pp. $26

Born in Brooklyn to Russian Jewish immigrant parents, Rostow became an academic achiever early in life. He entered Yale University at age 15, focused his studies on the economic theories of John Maynard Keynes, studied two years at Oxford University in England, then returned to Yale, where he earned his Ph.D. in 1940 with a dissertation titled "British Trade Fluctuations, 1868-1896."

Rostow began teaching at Columbia University, married a fellow scholar, served in World War II with the Office of Strategic Services spy agency, fathered children, helped draft a plan from a perch on the Continent for the recovery of European nations after the war, and eventually returned to the United States to settle in as a Massachusetts Institute of Technology professor after turning down an appointment at Harvard University.

Rostow developed a reputation as a pleasant human being and teacher, but his research focused outward, on international policymaking. According to Milne, Rostow eventually developed into an "anticommunist zealot." Some of Rostow's zealotry focused on the then barely recognizable nation of Vietnam, which had split into the communist north and the anticommunist south.

Rostow believed the U.S. government needed to reunite Vietnam under democratic, or at least anticommunist, rule. Although an admirer of democracy in the United States, Rostow did not seriously consider ballot-box democracy as a viable solution in Vietnam. Rather, he viewed military force as a solution, apparently indifferent to the deaths that would result among not only combatants but also civilians.

Living and teaching in the Boston area during the 1950s, Rostow became friendly with John F. Kennedy, the heir to a family fortune who had entered politics and was serving in the U.S. Senate.

When Kennedy became president of the United States, he wanted Rostow to join his administration, and Rostow wanted an invitation. Rostow would move to Washington, as deputy special assistant for national security affairs, placing him, as Milne says, "at the very center of executive power in the White House."

From the relative obscurity (as far as the general public knew) of that position, Rostow enjoyed access to the president and power to recommend war against the communist Soviet Union as well as its allies and satellite nations. Vietnam became Rostow's focal point; he recommended without qualification that the U.S. government drop bombs on North Vietnamese territory.

Kennedy and most of his other advisers rejected Rostow's hawkishness for a while. But Rostow began to make inroads. Then, Kennedy was dead, killed by an assassin's bullet. With Lyndon B. Johnson as the new president, Rostow's hawkish prescriptions began to prevail, with huge consequences for the North Vietnamese.

Johnson told the world that he would not be the president "who saw Southeast Asia go the same way China went" - that is, communist.

Eventually, Johnson suffered the consequences of his concordance with Rostow, whom he promoted within the bureaucracy. Significant portions of the American public turned against the Vietnam War and drove Johnson, along with Rostow, from the White House. By then, Rostow's hawkishness had contributed to thousands upon thousands of deaths and disabilities, with American soldiers, civilians, and their loved ones making up some of that total.

As Milne tells his narrative, he provides portraits of many others in the foreign policy realm, introducing Henry Kissinger, for example, as "vainglorious and brilliant" in his attempts to "fashion a diplomatic breakthrough where others had failed."

In addition, Milne relates Rostow's hawkishness within a Democratic Party context to the later hawkishness of advisers such as Richard Perle and Paul Wolfowitz within a Republican Party warmongering context.

Milne closes the book with an epilogue that explains how Rostow left government service reviled by many, but landed a position at the University of Texas thanks to Johnson's generosity.

In Austin, Rostow wrote book after book and article after article about the need for the U.S. government to exercise military as well as diplomatic strength.

If Rostow felt remorse, he hid it well.