William Daniel Leahy ( LAY-(h)ee; 6 May 1875 – 20 July 1959) was an American naval officer and was the most senior United States military officer on active duty during World War II; he held several titles and exercised considerable influence over foreign and military policy. As a fleet admiral, he was the first flag officer ever to hold a five-star rank in the U.S. Armed Forces.
An 1897 graduate of the United States Naval Academy, Leahy saw active service in the Spanish–American War, the Philippine–American War, the Boxer Rebellion in China, the Banana Wars in Central America, and World War I. He was the first member of his cadet class to reach flag rank, as the Chief of the Bureau of Ordnance from 1927 to 1931. He subsequently served as Chief of the Bureau of Navigation from 1933 to 1936, and commanded the Battle Fleet from 1936 to 1937. As Chief of Naval Operations from 1937 to 1939, he was the senior officer in the United States Navy, overseeing the expansion of the fleet and preparations for war.
After retiring from the Navy, Leahy was appointed the governor of Puerto Rico in 1939 by President Franklin D. Roosevelt. In his most controversial role, he served as the Ambassador to France from 1940 to 1942. American policy was aimed at keeping the government of Vichy France free of German control, but Leahy had limited success and came to believe the United States should back Free France instead of Vichy France. He asked to be recalled to the United States after the Japanese attack on Pearl Harbor brought the United States into the Second World War.
Leahy was recalled to active duty and became the Chief of Staff to President Roosevelt in 1942, serving in that position for the rest of the war. As the de facto first Chairman of the Joint Chiefs of Staff, he oversaw all of the American armed forces and was a major decision-maker during the war. He also presided over the American delegation to the Combined Chiefs of Staff. In December 1944, he was promoted to the five-star rank of fleet admiral. In the aftermath of World War II, he served Roosevelt's successor Harry S. Truman, helping shape postwar foreign policy until he retired in 1949. Although he did not oppose the use of the nuclear weapons during the war, in the post-war period he rejected war plans that overemphasised the first use of nuclear weapons.
William Daniel Leahy was born in Hampton, Iowa, on 6 May 1875, the first of seven children of Michael Anthony Leahy, a lawyer and American Civil War veteran, who was elected to the Iowa Legislature in 1872, and his wife Rose Mary née Hamilton. Both parents were born in the United States but his grandparents were immigrants from Ireland. He had five brothers and a sister. His father was re-elected in 1874, but moved to Wausau, Wisconsin, in 1882. In 1889, the family moved again, this time to Ashland, Wisconsin, where Leahy attended high school. His nose was broken in an American football match and his family lacked the money to get it fixed, so it remained crooked for the rest of his life.
Leahy wanted to attend the United States Military Academy at West Point, New York, but this required a Congressional appointment, and Leahy was unable to secure one. His local congressman, Thomas Lynch, offered Leahy an appointment to the United States Naval Academy in Annapolis, Maryland, which was much less popular among boys in the landlocked Midwest. Leahy passed the entrance examinations and was admitted as a naval cadet in May 1893.
Leahy learned how to sail on the USS Constellation on a summer cruise to Europe, although the vessel only made it as far as the Azores before breaking down. He graduated 35th out of 47 in the class of 1897. His class was the most successful ever: Five of its members reached four-star rank while on active duty: Leahy, Thomas C. Hart, Arthur J. Hepburn, Orin G. Murfin, and Harry E. Yarnell. As of 2022, no other class has had more than four.
Until 1912, naval cadets graduating from Annapolis had to complete two years' duty at sea and pass examinations before they could be commissioned as ensigns. Leahy was assigned to the battleship USS Oregon, which was then at Vancouver, British Columbia, for celebrations of Queen Victoria's Diamond Jubilee. He was on board when she made a dash through the Strait of Magellan, and around South America in the spring of 1898 to participate in the Spanish–American War. The Oregon took part in the blockade and bombardment of Santiago and shelled the small town of Guantánamo, which Leahy felt was "unnecessary and cruel." In the Battle of Santiago on 3 July, Leahy was in command of the ship's forward turret. This was the only naval battle Leahy witnessed in person.
Seeking further action, Leahy volunteered to serve on the gunboat USS Castine. The ship was bound for the war in the Pacific, traveling via the Mediterranean Sea and Suez Canal, but he got only as far as Ceylon when he received orders to report to Annapolis for his final ensign's examinations. He was left at Ceylon, and had to return to the United States on the USS Buffalo. He reached Annapolis in June 1899. He passed his examinations, and was commissioned as an ensign on 1 July 1899. After a few weeks' leave, spent with his parents in Wisconsin, and a few months' service on the cruiser USS Philadelphia at the Mare Island Navy Yard, he joined the monitor USS Nevada on 12 October 1899. A week later it set sail for the Philippines. It arrived in Manila on 24 November, and Leahy rejoined the crew of the Castine five days later.
China and Philippine–American Wars
On 17 December 1899, Castine sailed for Nagasaki, but it developed engine trouble on 12 February 1900 and stopped in Shanghai to make repairs. While it was there, the Boxer Rebellion broke out in China; the ship was retained in Shanghai to help British, French and Japanese forces guard the city. Leahy did not like their chances if the 4,500 Chinese troops in the vicinity joined the uprising, as they had in the Battle of Tientsin. On 28 August, the Castine was ordered to Amoy to protect American interests in fear of a Japanese coup. After the threat had passed, the Castine returned to the Philippines, arriving back in Manila on 16 September 1900.
The Philippine–American War was still ongoing, and the Castine supported American operations on Marinduque and Iloilo. Leahy was appalled by American brutality and the widespread use of torture. Still an ensign, he was given his first command, the gunboat USS Mariveles, a refitted ex-Spanish vessel. It had a crew of 23. His period in command ended when the Mariveles lost one of its propellers and had to be laid up for repairs. He was then reassigned to the USS Glacier, a stores ship which was engaged in bringing supplies from Australia to the Philippines. While in the Philippines he passed the examinations required for promotion to lieutenant, junior grade, and was promoted to that rank on 1 July 1902. He made his final trip to the Philippines in September 1902, and returned to the United States later that year.
Sea duty alternated with duty ashore. Leahy was assigned to the training ship USS Pensacola in San Francisco, where he was promoted to lieutenant on 31 December 1903. He met and courted Louise Tennent Harrington. Leahy married Louise on 3 February 1904. Louise subsequently convinced him to convert to Episcopalianism.
Leahy helped commission the cruiser USS Tacoma but swapped assignments with an officer on the USS Boston so that he could remain in San Francisco with Louise, who was pregnant. Over the next two years the Boston cruised back and forth between San Francisco and Panama, where the Panama Canal was under construction. He was in Acapulco when their son and only child, William Harrington Leahy, was born on 27 October 1904, and did not see his son until five months later. He was present for the 1906 San Francisco earthquake. His family had to leave their house in the face of the resulting fires. It survived undamaged, although they had to live in a hotel for several months before they could return.