War Plan Orange (commonly known as Plan Orange or just Orange) was a series of

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

Joint Army and Navy Board war plans for dealing with a possible war with

Imperial Japan The Empire of Japan, also known as the Japanese Empire or Imperial Japan, was the Japanese nation state that existed from the Meiji Restoration on January 3, 1868, until the Constitution of Japan took effect on May 3, 1947. From Japan–Kor ...

during the years between the First and Second World Wars. It failed to foresee the significance of the technological changes to

naval warfare Naval warfare is combat in and on the sea, the ocean, or any other battlespace involving a major body of water such as a large lake or wide river. The Military, armed forces branch designated for naval warfare is a navy. Naval operations can be ...

, including the

submarine A submarine (often shortened to sub) is a watercraft capable of independent operation underwater. (It differs from a submersible, which has more limited underwater capability.) The term "submarine" is also sometimes used historically or infor ...

, air support and

aircraft carriers An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering shipborne aircraft. Typically it is the capital ship of a fl ...

, and although the

Battle of Midway The Battle of Midway was a major naval battle in the Pacific Ocean theater of World War II, Pacific Theater of World War II that took place on 4–7 June 1942, six months after Japan's attack on Pearl Harbor and one month after the Battle of t ...

was important, and the

US Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

did " island-hop" to regain lost territory, there was no culminating "showdown" battle as anticipated by Plan Orange.

Development

Informal studies as early as 1906 covered a number of possibilities, from basing at

Gibraltar Gibraltar ( , ) is a British Overseas Territories, British Overseas Territory and British overseas cities, city located at the southern tip of the Iberian Peninsula, on the Bay of Gibraltar, near the exit of the Mediterranean Sea into the A ...

Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...

(an idea revived by the British before World War II) to "a quick trans-Atlantic dash" to the Pacific.Holwitt, p.131. The plan eventually adopted was conceived by Rear Admiral Raymond P. Rodgers in 1911. * 19 Dec 1919: Strategy of the Pacific (JB 325, Serial 28) * 7 Jul 1923: Estimate of the Situation, Orange (JB 325, Serial 207) * 15 Aug 1924: Joint Basic War Plan - Orange (JB 325, Serial 228) * 10 Jan 1929: Revision of Joint Army and Navy Basic War Plan Orange (JB 325, Serial 280) * 20 Jun 1934: Inadequacy of Present Military and Naval Forces Philippine Area to Carry Out Assigned Missions in Event of an ORANGE War (JB 325, Serial 533) * 8 May 1935: Revision of Joint Army and Navy Basic War Plan - Orange (JB 325, Serial 546) * 19 May 1935: Revision of Joint Army and Navy Basic War Plan - Orange (JB 325, Serial 570) * 14 Oct 1936: Revision of Joint Orange Estimate of the Situation (JB 325, Serial 589) * 9 Dec 1936: Changes in Joint Basic War Plan Orange (JB 325, Serial 594) * 19 Feb 1938: Joint Army and Navy Basic War Plan Orange (1938) (JB 325, Serials 617 & 618) The plan was formally adopted by the Joint Army and Navy Board beginning in 1924. Predating the Rainbow plans, which presumed the assistance of allies, Orange assumed that the United States would fight Japan alone.

Strategy

As originally conceived, it anticipated a blockade of the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

and other U.S. outposts in the western Pacific. They were expected to hold out on their own while the Pacific Fleet marshaled its strength at bases in

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

and guarded against attacks on the

Panama Canal The Panama Canal () is an artificial waterway in Panama that connects the Caribbean Sea with the Pacific Ocean. It cuts across the narrowest point of the Isthmus of Panama, and is a Channel (geography), conduit for maritime trade between th ...

. After mobilization (the ships maintained only half of their crews in peacetime), the fleet would sail to the western Pacific to relieve American forces in

Guam Guam ( ; ) is an island that is an Territories of the United States, organized, unincorporated territory of the United States in the Micronesia subregion of the western Pacific Ocean. Guam's capital is Hagåtña, Guam, Hagåtña, and the most ...

and the Philippines. Afterwards, the fleet would sail north for a decisive battle against the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, Potsdam Declaration, when it was dissolved followin ...

Combined Fleet The was the main sea-going component of the Imperial Japanese Navy. Until 1933, the Combined Fleet was not a permanent organization, but a temporary force formed for the duration of a conflict or major naval maneuvers from various units norm ...

and then blockade the Japanese home islands. The strategy was in keeping with the theory of

Alfred Thayer Mahan Alfred Thayer Mahan (; September 27, 1840 – December 1, 1914) was a United States Navy officer and historian whom John Keegan called "the most important American strategist of the nineteenth century." His 1890 book '' The Influence of Sea Pow ...

, a doctrine to which every major navy subscribed before World War II in which wars would be decided by engagements between opposing surface fleets (as they had been for over 300 years). Following the 1933 Operations IV

Wargame A normal wargame is a strategy game in which two or more players command opposing armed forces in a simulation of an armed conflict. Wargaming may be played for Recreational wargaming, recreation, to train military officers in the art of milit ...

, which resulted in defeat for a hypothetical blue fleet meant to symbolize a US Philippine relief force, War Plan Orange was revised to account for a more steady, methodical advance in order to take Japanese strongpoints in the

Marshall Islands The Marshall Islands, officially the Republic of the Marshall Islands, is an island country west of the International Date Line and north of the equator in the Micronesia region of the Northwestern Pacific Ocean. The territory consists of 29 c ...

. This was done in accordance to observations that both stretched logistical capacity in the "through ticket to the Philippines" strategy, and inability to repair damaged vessels, allowed Japan to gain

command of the sea Command of the sea (also called control of the sea or sea control) is a naval military concept regarding the strength of a particular navy to a specific naval area it controls. A navy has command of the sea when it is so strong that its rivals ...

via the neutralization of the US battle line force. Despite this, the strategy followed by the U.S. in the

Pacific War The Pacific War, sometimes called the Asia–Pacific War or the Pacific Theatre, was the Theater (warfare), theatre of World War II fought between the Empire of Japan and the Allies of World War II, Allies in East Asia, East and Southeast As ...

differed little from Rodgers' concept from 1911: a "leapfrog" campaign to conquer the Marshalls and Carolines (held by Japan before the war); liberation of the Philippines; and blockade. Absent was the "decisive battle" of Mahan, and of Japanese planning.

Japanese plans

In accordance with the '' Kantai Kessen'' naval strategy, the Imperial Japanese Navy developed its own plan that allowed the US Pacific Fleet to sail across the Pacific while the IJN would use submarines and carrier attacks to weaken it. The Japanese fleet would then attempt to force a fleet action against the weakened US fleet in a "decisive battle area", near Japan, also in line with Mahanian doctrine, which Japan had enthusiastically embraced. It was the basis for Japan's demand for a 70% ratio (10:10:7) at the

Washington Naval Conference The Washington Naval Conference (or the Washington Conference on the Limitation of Armament) was a disarmament conference called by the United States and held in Washington, D.C., from November 12, 1921, to February 6, 1922. It was conducted out ...

, which was considered necessary to provide Japan superiority in the "decisive battle area" (taking into account that the US had naval commitments in other theaters, while Japan did not). It was also the basis of the United States' insistence on 60%, which amounted to parity.

Outcomes

Actual events generally followed the plan. Although carrier battles and the use of airplanes and submarines overshadowed surface action, the "leapfrog" campaign played out largely as anticipated. The Imperial Japanese Navy, obsessed with the "decisive battle" doctrine, ignored the vital need for defense against submarines. The German and American submarine campaigns against their opponents' merchant shipping demonstrated the need for an anti-submarine warfare strategy. While the Allies took extensive measures to combat the threat of German

U-boat U-boats are Submarine#Military, naval submarines operated by Germany, including during the World War I, First and Second World Wars. The term is an Anglicization#Loanwords, anglicized form of the German word , a shortening of (), though the G ...

s, the Japanese failed to effectively counter the American submarines which ultimately choked Japan's industrial production and paralyzed her navy. Japan also notably failed to institute an anti-commerce campaign where systematic use of commerce raiders could have made Allied operations much more complex and conquering and holding Japanese-held islands more difficult. American war planners failed to appreciate that technological advances in submarines and

naval aviation Naval aviation / Aeronaval is the application of Military aviation, military air power by Navy, navies, whether from warships that embark aircraft, or land bases. It often involves ''navalised aircraft'', specifically designed for naval use. Seab ...

had made Mahan's doctrine obsolete and did not anticipate a preemptive strike from the Japanese. In particular, they did not yet know either that aircraft would be able to effectively sink battleships or that Japan might put the American battleship force (the Battle Line) out of action at a stroke, which actually happened at Pearl Harbor on December 7, 1941. American plans changed after this attack. Even after major Japanese defeats like Midway, once the effectiveness of aircraft carriers was known, the Americans favored a methodical "island-hopping" advance, never going far beyond land-based air cover. Meanwhile, a blockade was imposed from the very beginning of the war, with the first American submarine, , arriving off Japan on about 31 December 1941. A number of requirements grew out of Orange, including the specification for a

fleet submarine A fleet submarine is a submarine with the speed, range, and endurance to operate as part of a navy's battle fleet. Examples of fleet submarines are the British First World War era K class and the American World War II era ''Gato'' class. The ...

with high speed, long range, and heavy torpedo armament. These coalesced in the submarine in 1932 (only to be rejected and returned to with the in around August 1941). The demand for submarines of this size also drove the development of the notoriously problematic Mark 14 torpedo (and its equally notorious Mark VI exploder), under the guidance of CommanderHolwitt, p.147fn52. Ralph W. Christie.Blair, p.61. The Navy also spent "several hundred thousand dollars" to develop powerful, compact diesel engines, among them the troublesome Hooven-Owens-Rentschler, which proved useful for railroads.

Development

Strategy

Japanese plans

Outcomes

See also

References

Further reading