Leapfrogging (military)
Encyclopedia
Leapfrogging was a military strategy employed by the Allies
in the Pacific War
against Japan
and the Axis powers
during World War II
. The idea was to bypass heavily fortified Japanese
positions and instead concentrate the limited Allied resources on strategically important island
s that were not well defended but capable of supporting the drive to the main islands of Japan
.
and Guam
-- which the U.S. had gained as a result of the Spanish–American War (1898). After Japan's victories in the Sino-Japanese War
(1894–1895) and in the Russo-Japanese War
of 1904, the U.S. began to regard Japan as a potential threat to its interests in the western Pacific. This antagonism was intensified by Japan's objections to an attempt to annex Hawaii to the U.S. (1893) and by Japan's objections to discrimination against Japanese immigrants in Hawaii (1897) and California (1906, 1913). As a result, the U.S. Navy began to draft, as early as 1897, war plans against Japan, which were eventually code-named "War Plan Orange
". The war plan of 1911, which was drafted under Rear Admiral Raymond P. Rodgers
, included an island-hopping strategy for approaching Japan.
After World War I, the Versailles Treaty
gave Japan a mandate over former German colonies in the western Pacific; specifically, the Mariana
, Marshall
, and Caroline
Islands. If these islands were fortified, Japan could, in principle, deny the U.S. access to its interests in the western Pacific. Therefore, in 1921, Lieutenant Colonel Earl H. Ellis
of the U.S. Marine Corps drafted "Plan 712, Advanced Base Operations in Micronesia," a plan for war against Japan which updated War Plan Orange by incorporating modern military technology (submarines, aircraft, etc.) and which again included an island-hopping strategy. Shortly afterwards, a British-American reporter on naval affairs, Hector C. Bywater
, publicized the prospect of a Japanese-American war in his books Seapower in the Pacific (1923) and The Great Pacific War
(1925), which detailed an island-hopping strategy. The books were read not only by Americans but by senior officers of the Japanese Imperial Navy, who used "island-hopping" in their successful southeast Asia offensives in 1941 and 1942.
and air attacks to blockade
and isolate Japanese bases, weakening their garrisons and reducing the Japanese ability to resupply and reinforce them. Thus troops on islands which had been bypassed, such as the major base at Rabaul
, were useless to the Japanese war effort and left to "wither on the vine." General Douglas MacArthur greatly supported this strategy in his effort to regain the Philippines
. This strategy began to be implemented in late 1943 in Operation Cartwheel
. While General Douglas MacArthur claimed to have invented the strategy, it initially came out of the Navy.
and Marshall Islands
and the Marianas, going generally in the direction of the Bonin Islands. The southern prong, led by General MacArthur and with larger land forces, would take the Solomons
, New Guinea
, the Bismarck Archipelago
, advancing toward the Philippines.
after capturing the northern Philippines
, and when he instigated the reconquest of portions of Borneo
, he violated the "basic tenets" of island hopping. In the first case, this may have been motivated by MacArthur's promise to return to the people of the Philippines as soon as possible.
Allies of World War II
The Allies of World War II were the countries that opposed the Axis powers during the Second World War . Former Axis states contributing to the Allied victory are not considered Allied states...
in the Pacific War
Pacific War
The Pacific War, also sometimes called the Asia-Pacific War refers broadly to the parts of World War II that took place in the Pacific Ocean, its islands, and in East Asia, then called the Far East...
against Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
and the Axis powers
Axis Powers
The Axis powers , also known as the Axis alliance, Axis nations, Axis countries, or just the Axis, was an alignment of great powers during the mid-20th century that fought World War II against the Allies. It began in 1936 with treaties of friendship between Germany and Italy and between Germany and...
during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. The idea was to bypass heavily fortified Japanese
Imperial Japanese Army
-Foundation:During the Meiji Restoration, the military forces loyal to the Emperor were samurai drawn primarily from the loyalist feudal domains of Satsuma and Chōshū...
positions and instead concentrate the limited Allied resources on strategically important island
Island
An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...
s that were not well defended but capable of supporting the drive to the main islands of Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
.
Background
By the late nineteenth century, the U.S. had several interests in the western Pacific to defend; namely, access to the Chinese market, and colonies—the PhilippinesPhilippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
and Guam
Guam
Guam is an organized, unincorporated territory of the United States located in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Guam is listed as one of 16 Non-Self-Governing Territories by the Special Committee on Decolonization of the United...
-- which the U.S. had gained as a result of the Spanish–American War (1898). After Japan's victories in the Sino-Japanese War
First Sino-Japanese War
The First Sino-Japanese War was fought between Qing Dynasty China and Meiji Japan, primarily over control of Korea...
(1894–1895) and in the Russo-Japanese War
Russo-Japanese War
The Russo-Japanese War was "the first great war of the 20th century." It grew out of rival imperial ambitions of the Russian Empire and Japanese Empire over Manchuria and Korea...
of 1904, the U.S. began to regard Japan as a potential threat to its interests in the western Pacific. This antagonism was intensified by Japan's objections to an attempt to annex Hawaii to the U.S. (1893) and by Japan's objections to discrimination against Japanese immigrants in Hawaii (1897) and California (1906, 1913). As a result, the U.S. Navy began to draft, as early as 1897, war plans against Japan, which were eventually code-named "War Plan Orange
War Plan Orange
War Plan Orange refers to a series of United States Joint Army and Navy Board war plans for dealing with a possible war with Japan during the years between the First and Second World Wars....
". The war plan of 1911, which was drafted under Rear Admiral Raymond P. Rodgers
Raymond P. Rodgers
Rear Admiral Raymond Perry Rodgers was an officer in the United States Navy. He succeeded Lt. Theodorus B.M. Mason as the second head of the Office of Naval Intelligence....
, included an island-hopping strategy for approaching Japan.
After World War I, the Versailles Treaty
Treaty of Versailles
The Treaty of Versailles was one of the peace treaties at the end of World War I. It ended the state of war between Germany and the Allied Powers. It was signed on 28 June 1919, exactly five years after the assassination of Archduke Franz Ferdinand. The other Central Powers on the German side of...
gave Japan a mandate over former German colonies in the western Pacific; specifically, the Mariana
Mariana Islands
The Mariana Islands are an arc-shaped archipelago made up by the summits of 15 volcanic mountains in the north-western Pacific Ocean between the 12th and 21st parallels north and along the 145th meridian east...
, Marshall
Marshall Islands
The Republic of the Marshall Islands , , is a Micronesian nation of atolls and islands in the middle of the Pacific Ocean, just west of the International Date Line and just north of the Equator. As of July 2011 the population was 67,182...
, and Caroline
Caroline Islands
The Caroline Islands are a widely scattered archipelago of tiny islands in the western Pacific Ocean, to the north of New Guinea. Politically they are divided between the Federated States of Micronesia in the eastern part of the group, and Palau at the extreme western end...
Islands. If these islands were fortified, Japan could, in principle, deny the U.S. access to its interests in the western Pacific. Therefore, in 1921, Lieutenant Colonel Earl H. Ellis
Earl Hancock Ellis
Lieutenant Colonel Earl Hancock "Pete" Ellis was a United States Marine Corps Intelligence Officer, and author of , which became the basis for the American campaign of amphibious assault that defeated the Japanese in World War II...
of the U.S. Marine Corps drafted "Plan 712, Advanced Base Operations in Micronesia," a plan for war against Japan which updated War Plan Orange by incorporating modern military technology (submarines, aircraft, etc.) and which again included an island-hopping strategy. Shortly afterwards, a British-American reporter on naval affairs, Hector C. Bywater
Hector Charles Bywater
Hector Charles Bywater was a British journalist and military writer.H.C. Bywater was the second son of a middle class Welshman. The family had emigrated into the United States in 1901...
, publicized the prospect of a Japanese-American war in his books Seapower in the Pacific (1923) and The Great Pacific War
The Great Pacific War
′The Great Pacific War was a 1925 novel by Hector Charles Bywater which discussed a hypothetical future war between Japan and the United States. The novel accurately predicts a number of details about the Pacific Campaign of World War II...
(1925), which detailed an island-hopping strategy. The books were read not only by Americans but by senior officers of the Japanese Imperial Navy, who used "island-hopping" in their successful southeast Asia offensives in 1941 and 1942.
Rationale and use
This strategy was possible in part because the Allies used submarineSubmarine
A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...
and air attacks to blockade
Blockade
A blockade is an effort to cut off food, supplies, war material or communications from a particular area by force, either in part or totally. A blockade should not be confused with an embargo or sanctions, which are legal barriers to trade, and is distinct from a siege in that a blockade is usually...
and isolate Japanese bases, weakening their garrisons and reducing the Japanese ability to resupply and reinforce them. Thus troops on islands which had been bypassed, such as the major base at Rabaul
Rabaul
Rabaul is a township in East New Britain province, Papua New Guinea. The town was the provincial capital and most important settlement in the province until it was destroyed in 1994 by falling ash of a volcanic eruption. During the eruption, ash was sent thousands of metres into the air and the...
, were useless to the Japanese war effort and left to "wither on the vine." General Douglas MacArthur greatly supported this strategy in his effort to regain the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
. This strategy began to be implemented in late 1943 in Operation Cartwheel
Operation Cartwheel
Operation Cartwheel was a major military strategy for the Allies in the Pacific theater of World War II. Cartwheel was a twin-axis of advance operation, aimed at militarily neutralizing the major Japanese base at Rabaul...
. While General Douglas MacArthur claimed to have invented the strategy, it initially came out of the Navy.
Advantages
Leapfrogging had a number of advantages. It would allow the United States forces to reach Japan more quickly and not expend the time, manpower, and supplies to capture every Japanese-held island on the way. It would give the Allies the advantage of surprise and keep the Japanese off balance. The overall leapfrogging strategy would involve two prongs. A force led by Admiral Chester Nimitz, with a smaller land force and larger fleet, would advance north towards the island and capture the GilbertGilbert Islands
The Gilbert Islands are a chain of sixteen atolls and coral islands in the Pacific Ocean. They are the main part of Republic of Kiribati and include Tarawa, the site of the country's capital and residence of almost half of the population.-Geography:The atolls and islands of the Gilbert Islands...
and Marshall Islands
Marshall Islands
The Republic of the Marshall Islands , , is a Micronesian nation of atolls and islands in the middle of the Pacific Ocean, just west of the International Date Line and just north of the Equator. As of July 2011 the population was 67,182...
and the Marianas, going generally in the direction of the Bonin Islands. The southern prong, led by General MacArthur and with larger land forces, would take the Solomons
Solomon Islands
Solomon Islands is a sovereign state in Oceania, east of Papua New Guinea, consisting of nearly one thousand islands. It covers a land mass of . The capital, Honiara, is located on the island of Guadalcanal...
, New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, the Bismarck Archipelago
Bismarck Archipelago
The Bismarck Archipelago is a group of islands off the northeastern coast of New Guinea in the western Pacific Ocean and is part of the Islands Region of Papua New Guinea.-History:...
, advancing toward the Philippines.
Ignoring the principle
The principle of leapfrogging was not always followed in the Pacific. When MacArthur moved south to attack MindanaoMindanao
Mindanao is the second largest and easternmost island in the Philippines. It is also the name of one of the three island groups in the country, which consists of the island of Mindanao and smaller surrounding islands. The other two are Luzon and the Visayas. The island of Mindanao is called The...
after capturing the northern Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
, and when he instigated the reconquest of portions of Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
, he violated the "basic tenets" of island hopping. In the first case, this may have been motivated by MacArthur's promise to return to the people of the Philippines as soon as possible.