Phillips O'Brien

Phillips Payson O'Brien (born 1963) is an American historian and professor of strategic studies at the University of St Andrews, Scotland. He was formerly at the University of Glasgow where he ran the Scottish Centre for War Studies. His books include the revisionist history How the War Was Won: Air-Sea Power and Allied Victory in World War II (2015) which concluded that superiority in the air and on the sea on an "Air-Sea Super Battlefield" of thousands of miles, rather than battles on land, determined the outcome of the war. He is also the author of The Second Most Powerful Man in the World: The Life of Admiral William D. Leahy, Roosevelt's Chief of Staff (2019) which re-evaluated the life of Leahy and argued that he was far more influential than had previously been recognised.