The Sailor Who Brought Victory in WWII

Naval Cadet William D. Leahy, 1898 off Santiago.

Review by Bill Doughty

A Sailor was center-stage both in winning World War II and in setting up a successful strategy for the Cold War.

Some historians see Fleet Admiral William D. Leahy as a figure in the background, but he was in fact a key strategic thinker, planner and leader as Chief of Naval Operations, chief of staff to President Franklin D. Roosevelt, chairman of the joints chiefs of staff, national security advisor, ambassador, and, with President Truman, creator of central intelligence for the United States.

Using hundreds of source documents and other resources, Phillips Payson O'Brien shows Leahy's phenomenal influence before, during and after the Second World War in "The Second Most Powerful Man in the World: The Life of Admiral William D. Leahy, Roosevelt's Chief of Staff" (Dutton, Penguin House, 2019).

Midshipman William Leahy graduated from the Naval Academy in 1897. He learned to sail aboard the USS Constellation.

President Taft visits U.S. Pacific Fleet on Navy's birthday, Oct. 15, 1911 with aide, Lt. Cmdr. Leahy. 

He would become the highest ranking American military officer to have served aboard the Constellation when the United States dropped the first atomic bombs in 1945.

Early in his career Leahy served in China, in the Spanish-American War, in the Philippines Insurrection, and during what was called the Banana War in Nicaragua. As a lieutenant commander, he became aide to President William Howard Taft.

Serving aboard warships in World War I and in overseas diplomatic assignments, big and small, Leahy gained an international perspective. He and Roosevelt bonded when the future president was assistant secretary of the Navy and later during FDR's 12-year presidency.

"Sharing a similar outlook on the world, Leahy and Roosevelt melded from the start. Both were convinced of the need for a large and efficient U.S. Navy. Roosevelt had manifested a love of the sea since boyhood and was fascinated with the importance of sea power. He was a believer in the historical theories of Alfred Thayer Mahan, the American naval officer who argued in the late nineteenth century that sea power was the greatest determinant in world politics. Mahan's ideas became fashionable and spread across the globe, influencing thanking not just in America but in Europe and Asia as well. In a series of books on various periods of history, he posited that control of the seas was practically an immutable law of international relations; that nations such as Great Britain, which could exercise dominance on the world's oceans, would inevitably triumph over other countries that could not. For Americans like Roosevelt and Leahy, Mahan helped codify an instinctive belief that the United States needed a much stronger fleet. When Roosevelt became assistant secretary [of the Navy], he engaged in a correspondence with Mahan about sea power, and, with war looming in Europe, the need to popularize its value. Yet Roosevelt, like Leahy, did not believe in sea power as part of some imperialist drive to conquer. He saw sea power as something vital to the United States' security, regardless of whether an American empire existed or not."

"By the late summer of 1937, Leahy was entrenched as the most powerful CNO in naval history," O'Brien writes. During the war, he became "the most powerful chairman of the joint chiefs of staff in American history, with or without congressional authorization." After the war he set out a plan to work with partners and Allies for a lasting peace.

Leahy's legacy:

• Embraced new technologies – In the 1930s, as tensions rose in Europe and Asia, Leahy led development of anti-aircraft defenses, a prescient and lifesaving move.
• Developed key alliances within government – Leahy built ties with FDR, Sumner Welles in the State Department, and congressional leaders like Carl Vinson, who had a "political tenacity on behalf of the fleet."
• Arranged allocation of resources – Thanks to Leahy's influence, new ships were built, including 60,000 tons of new cruisers, 30,000 tons of new destroyers (crucial after the attack on Pearl Harbor), large mobile dry docks, and tankers to refuel forward-deployed aircraft carriers.
• Made the shift from battleships to aircraft carriers – Leahy ensured the Navy had resources, including the building of 15 CVs during World War II.
• Saw the strategic importance of Marianas, Philippines, Hawaii and Puerto Rico – Leahy was an early proponent of air- and sea-power and forward basing.
• Instilled decentralized merit-based leadership – Throughout his career, Leahy pushed for a flattened organization. He pushed up young talented officers and pushed out older, less competent ones.
• Insisted on a purposeful blockade of Japan – When Nazi Germany and Imperial Japan conspired to invade Indochina (Vietnam) to take oil and other resources, Leahy, Welles and FDR planned for the embargo.
• Chose naval leaders – Immediately after Pearl Harbor and Oahu were attacked, Leahy wrote to FDR with his suggestions of Ernest King, Chester Nimitz and Thomas Hart for key positions in "important naval commands."
• Corralled the strong personalities of military leaders – Leahy had the unenviable job of soothing inter-service rivalries, type-A personalities and conflicting rivalries of General George C. Marshall, General Henry "Hap" Arnold, Adm. Ernest King, General Douglas MacArthur and other military leaders, including especially those of Allied nations.
• Balanced the needs of the military with labor market – Leahy opposed conscripting and nationalizing civilian companies and workers, and he defended civil liberties in the face of authoritarian tendencies of the government during the war.
• Developed a strategy of air- and sea-power to defeat Fascist Italy, Nazi Germany and Imperial Japan – His strategy worked to near perfection within a few years. O'Brien documents Leahy's direct influence.
• Opposed large-scale invasion of Japan – Leahy opposed both a direct assault on mainland Japan and the proposed use of a biological weapon designed to destroy rice. And he was against the atom bomb targeting noncombatants. "War is not to be waged to wipe out women and children," Leahy wrote.
• Foresaw problems with U.S. involvement in the Middle East – Leahy viewed emigration of Jewish refugees to Palestine as a mistake, and he argued against getting involved in other countries' civil wars, particularly among Islamic states.
• Warned of the dangers of Communist China – Leahy lamented the U.S. failure to back up the Chinese nationalists fighting the Communist takeover, which he considered, "the greatest American foreign policy tragedy of his career." The takeover led directly to the Korean War and creation of North Korea.
• Warned of the dangers of an untruthful, untrusting and untrustworthy Russia – From Appendix 3 (Leahy's notes on relations with USSR): "In secretive atmosphere pervading Soviet Govt., possibilities for distorting truth are infinite. The Russians do not believe in the existence of objective truth and hence believe all statements to be cloak for some ulterior motive."
• Fought the "unification" of the armed forces – Immediately after WWII, the Army proposed absorbing the Marine Corps and having the Army Air Force take over naval aviation. Leahy helped the Navy successfully fend off the power grab, which he could have adversely affected a balanced civilian control of the military. "To Leahy, civilian control of the military was, as always, sacrosanct," O'Brien writes.
• Opposed an interventionist CIA – After losing influence late in his career, "Leahy watched helplessly while the CIA transformed into a force committed to widespread covert operations."
• Drafted a blueprint for postwar peace – See the Navy Reads post on how Leahy worked with President Truman for a Navy Day speech outlining Cold War strategies for cooperation and the importance of global alliances to prevent war.

Leahy stands behind FDR, seated between Churchill and Stalin at Yalta in 1945.

As FDR's key war planner, Leahy achieved the "grandest level of strategy," O'Brien writes:

"Historians relish rehashing the great strategic decisions that supposedly determined the outcome of World War II: Britain's resolve to fight on after the fall of France, Hitler's decision to invade the Ukraine instead of aiming for Moscow, Japan's doomed attack on Midway Island. Such choices add an air of suspense to the war, but they also miss the point about how modern war is won or lost. Decisions on when, where and even if can only be made after the careful determination of an even more important series of strategic choices, which represent the highest level of grand strategy, are about what kind of armed forces should be constructed. Every power in World War II had to assess what weaponry they needed to build their armies and navies, and, moreover, how to balance the need for military manpower with the necessity for industrial workers to assemble war machinery. Never do these decisions receive the intense focus reserved for the use of military force, but they are determinative."

O'Brien's biography is a priceless new look at a quiet giant in American history in the Twentieth Century. Leahy was a diplomat statesman who preferred the shadows to the limelight. In the best traditions of government service, Fleet Admiral Leahy led with humility, honor, honesty and strength.

(NOTE: Leahy was a staunch (and successful) defender of the U.S. Navy's war efforts in the Pacific, ensuring 90 percent of the Navy's assets were directed toward the war against Japan. Great Britain, on the other hand, believed the Allies should have a Germany-first policy. This led to a serious disagreement in meetings between the key Allies. "For Leahy, China was not to be abandoned, and his temper was put to the test when the British wheeled out Field Marshal Archibald Wavell. A repeated failure consistently promoted throughout his career as a way of moving him on. Wavell had been beaten soundly by Rommel in the Desert War of 1941 and deposited into India ..." British Field Marshall Wavell is mentioned in O'Brien's biography of Fleet Admiral Leahy, whose collection of poetry is a coming Navy Reads review. O'Brien and Leahy offer an unflattering picture of the British WWI military leader.)

Senior Officers of the U.S. Armed Forces make a radio broadcast in Washington, D.C., following the official announcement of Victory in Europe on 8 May 1945: General of the Army George C. Marshall, Chief of Staff, U.S. Army; Fleet Admiral William D. Leahy, Senior Member of the Joint Chiefs of Staff; and Fleet Admiral Ernest J. King, Chief of Naval Operations. (National Archives)