Book excerpt: Few American presidents have exercised their constitutional authority as commander in chief with more determination than Franklin D. Roosevelt. He intervened in military operations more often and to better effect than his contemporaries Churchill and Stalin, and maneuvered events so that the Grand Alliance was directed from Washington. In this expansive history, Eric Larrabee examines the extent and importance of FDR's wartime leadership through his key military leaders—Marshall, King, Arnold, MacArthur, Vandergrift, Nimitz, Eisenhower, Stilwell, and LeMay. Devoting a chapter to each man, the author studies Roosevelt's impact on their personalities, their battles (sometimes with each other), and the consequences of their decisions. He also addresses such critical subjects as Roosevelt's responsibility for the war and how well it achieved his goals. First published in 1987, this comprehensive portrait of the titans of the American military effort in World War II is available in a new paperback edition for the first time in sixteen years.