World War II
World War II known as the Second World War, was a global war that lasted from 1939 to 1945. The vast majority of the world's countries—including all the great powers—eventually formed two opposing military alliances: the Allies and the Axis. A state of total war emerged, directly involving more than 100 million people from over 30 countries; the major participants threw their entire economic and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. World War II was the deadliest conflict in human history, marked by 50 to 85 million fatalities, most of whom were civilians in the Soviet Union and China, it included massacres, the genocide of the Holocaust, strategic bombing, premeditated death from starvation and disease, the only use of nuclear weapons in war. Japan, which aimed to dominate Asia and the Pacific, was at war with China by 1937, though neither side had declared war on the other. World War II is said to have begun on 1 September 1939, with the invasion of Poland by Germany and subsequent declarations of war on Germany by France and the United Kingdom.
From late 1939 to early 1941, in a series of campaigns and treaties, Germany conquered or controlled much of continental Europe, formed the Axis alliance with Italy and Japan. Under the Molotov–Ribbentrop Pact of August 1939, Germany and the Soviet Union partitioned and annexed territories of their European neighbours, Finland and the Baltic states. Following the onset of campaigns in North Africa and East Africa, the fall of France in mid 1940, the war continued between the European Axis powers and the British Empire. War in the Balkans, the aerial Battle of Britain, the Blitz, the long Battle of the Atlantic followed. On 22 June 1941, the European Axis powers launched an invasion of the Soviet Union, opening the largest land theatre of war in history; this Eastern Front trapped most crucially the German Wehrmacht, into a war of attrition. In December 1941, Japan launched a surprise attack on the United States as well as European colonies in the Pacific. Following an immediate U. S. declaration of war against Japan, supported by one from Great Britain, the European Axis powers declared war on the U.
S. in solidarity with their Japanese ally. Rapid Japanese conquests over much of the Western Pacific ensued, perceived by many in Asia as liberation from Western dominance and resulting in the support of several armies from defeated territories; the Axis advance in the Pacific halted in 1942. Key setbacks in 1943, which included a series of German defeats on the Eastern Front, the Allied invasions of Sicily and Italy, Allied victories in the Pacific, cost the Axis its initiative and forced it into strategic retreat on all fronts. In 1944, the Western Allies invaded German-occupied France, while the Soviet Union regained its territorial losses and turned toward Germany and its allies. During 1944 and 1945 the Japanese suffered major reverses in mainland Asia in Central China, South China and Burma, while the Allies crippled the Japanese Navy and captured key Western Pacific islands; the war in Europe concluded with an invasion of Germany by the Western Allies and the Soviet Union, culminating in the capture of Berlin by Soviet troops, the suicide of Adolf Hitler and the German unconditional surrender on 8 May 1945.
Following the Potsdam Declaration by the Allies on 26 July 1945 and the refusal of Japan to surrender under its terms, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki on 6 and 9 August respectively. With an invasion of the Japanese archipelago imminent, the possibility of additional atomic bombings, the Soviet entry into the war against Japan and its invasion of Manchuria, Japan announced its intention to surrender on 15 August 1945, cementing total victory in Asia for the Allies. Tribunals were set up by fiat by the Allies and war crimes trials were conducted in the wake of the war both against the Germans and the Japanese. World War II changed the political social structure of the globe; the United Nations was established to foster international co-operation and prevent future conflicts. The Soviet Union and United States emerged as rival superpowers, setting the stage for the nearly half-century long Cold War. In the wake of European devastation, the influence of its great powers waned, triggering the decolonisation of Africa and Asia.
Most countries whose industries had been damaged moved towards economic expansion. Political integration in Europe, emerged as an effort to end pre-war enmities and create a common identity; the start of the war in Europe is held to be 1 September 1939, beginning with the German invasion of Poland. The dates for the beginning of war in the Pacific include the start of the Second Sino-Japanese War on 7 July 1937, or the Japanese invasion of Manchuria on 19 September 1931. Others follow the British historian A. J. P. Taylor, who held that the Sino-Japanese War and war in Europe and its colonies occurred and the two wars merged in 1941; this article uses the conventional dating. Other starting dates sometimes used for World War II include the Italian invasion of Abyssinia on 3 October 1935; the British historian Antony Beevor views the beginning of World War II as the Battles of Khalkhin Gol fought between Japan and the fo
The Kenpeitai was the military police arm of the Imperial Japanese Army from 1881 to 1945. It was both a secret police force. During the Japanese occupation, the kenpeitai arrested those who were suspected of being anti-Japanese. While it was institutionally part of the army, the Kenpeitai discharged the functions of the military police for the Imperial Japanese Navy under the direction of the Admiralty Minister, those of the executive police under the direction of the Interior Minister and those of the judicial police under the direction of the Justice Minister. A member of the corps was called a kenpei; the Kenpeitai was established in 1881 by a decree called the Kenpei Ordinance, figuratively "articles concerning gendarmes". Its model was the Gendarmerie of France. Details of the Kenpeitai's military and judicial police functions were defined by the Kenpei Rei of 1898, amended twenty-six times before Japan's defeat in August 1945; the force consisted of 349 men. The enforcement of the new conscription legislation was an important part of their duty, due to resistance from peasant families.
The Kenpeitai's general affairs branch was in charge of the force's policy, personnel management, internal discipline, as well as communication with the Ministries of the Admiralty, the Interior, Justice. The operation branch was in charge of the distribution of military police units within the army, general public security and intelligence. In 1907, the Kenpeitai was ordered to Korea where its main duty was defined as "preserving the peace", although it functioned as a military police for the Japanese army stationed there; this status remained unchanged after Japan's annexation of Korea in 1910. The Kenpeitai maintained public order within Japan under the direction of the Interior Minister, in the occupied territories under the direction of the Minister of War. Japan had a civilian secret police force, Tokkō, the Japanese acronym of Tokubetsu Kōtō Keisatsu part of the Interior Ministry. However, the Kenpeitai had a Tokkō branch of its own, through it discharged the functions of a secret police.
When the Kenpeitai arrested a civilian under the direction of the Justice Minister, the arrested person was nominally subject to civilian judicial proceedings. The Kenpeitai's brutality was notorious in Korea and the other occupied territories; the Kenpeitai were abhorred in Japan's mainland as well during World War II when Prime Minister Hideki Tojo the Commander of the Kenpeitai of the Japanese Army in Manchuria from 1935 to 1937, used the Kenpeitai extensively to make sure that everyone was loyal to the war. According to United States Army TM-E 30-480, there were over 36,000 regular members of the Kenpeitai at the end of the war; as many foreign territories fell under the Japanese military occupation during the 1930s and the early 1940s, the Kenpeitai recruited a large number of locals in those territories. Taiwanese and Koreans were used extensively as auxiliaries to police the newly occupied territories in Southeast Asia, although the Kenpeitai recruited French Indochinese and others; the Kenpeitai may have trained a Vietnamese nationalist and military leader.
The Kenpeitai was disarmed and disbanded after the Japanese surrender in August 1945. Today, the post-war Self-Defense Forces' internal police is called Keimutai; each individual member is called Keimukan. In the 1920s and the 1930s, the Kenpeitai forged various connections with certain prewar European intelligence services; when Japan signed the Tripartite Pact, Japan formed formal links with the intelligence units, now under German and Italian fascists, known as the German Abwehr and the Italian Servizio Informazioni Militare. The army and the navy of Japan contacted their corresponding Wehrmacht intelligence units, Schutzstaffel or Kriegsmarine, about information on Europe and vice versa. Europe and Japan realized the benefits of the exchanges. For example, the Japanese sent data about Soviet forces in the Far East and in Operation Barbarossa from the Japanese embassy. Admiral Canaris offered aid in respect to the neutrality of Portugal in Timor. One important contact point was in occupied British Malaya.
The base served Axis submarine forces. At regular intervals and information exchanges occurred there. While these were available to them, Axis forces used the bases in Italian East Africa, the Vichy France colony of Madagascar and some neutral places like Portuguese India; the Kenpeitai ran extensive criminal and collaborationist networks, extorting vast amounts of money from businesses and civilians wherever they operated. They ran the Allied prisoner of war system, which treated captives with extreme brutality. Many of the abuses were documented in Japanese war crimes trials, such as those committed by the Kempeitai East District Branch in Singapore; the Kenpeitai carried out revenge attacks against prisoners and civilians. For example, after Colonel Doolittle's raid on Tokyo in 1942, the Kenpeitai carried out reprisals against thousands of Chinese civilians and captured airmen, or in 1943 the Double Tenth massacre, in response to an Allied raid on Singapore Harbour. All these actions together—including Unit 731's vivisection campaign—have become infamous.
The Kenpeitai maintained a headquarters in each re
Special Naval Landing Forces
The Special Naval Landing Forces, were the marine troops of the Imperial Japanese Navy and were a part of the IJN Land Forces. They saw extensive service in the Second Sino-Japanese War and the Pacific theatre of World War II. Before the late 1920s the IJN did not have a separate marine force, instead it used naval landing forces or rikusentai formed from individual ships's crews, who received infantry training as part of their basic training, for special and/or temporary missions. In the late 1920s the navy began to form Special Naval Landing Forces as standing regiments; these forces were raised at — and took their names from — the four main naval districts/bases in Japan: Kure, Maizuru and Yokosuka. These SNLF units saw action in China from 1932 in the January 28 Incident and at the Battle of Shanghai in naval operations along the China coast and up the Yangtze River and its tributaries during the Second Sino-Japanese War. Soon, they became involved in successful Japanese seaborne assaults throughout South East Asia.
Other SNLF were raised from IJN personnel in China, at Hankow, Shanghai, for service in Canton and on the Yangtze River. On 7 December 1941 there were 16 SNLF units, this increased to 21 units during the war; the strengths of each SNLF ranged from the prewar peak of 1,200 to a 650 personnel. There was a special detachment in the Kwantung area, garrisoning the ports of Dairen and Ryojun; the SNLF were not a marine force, but was instead sailors who had basic infantry training and were employed in landings during the Russo-Japanese War and the Boxer Rebellion. Soon their training and equipment were improved upon drastically, their forces were given a variety of other operations as well. In 1941, the 1st, 2nd and 3rd Yokosuka SNLF were converted to parachute units, they conducted more combat drops than Japanese Army parachute units during World War II. The SNLF paratroopers were used during the attack on Celebes and the Battle of Manado. Aside from the paratroopers, there were elite squads who conducted reconnaissance and raid operations.
From that point onward, the Landing Forces were influential in Japan's expansion of territories, their tactics of surprising their enemies through sea invasions proved effective. The original SNLF personnel were well-trained, high quality troops with good morale and they performed well against opposition across Southeast Asia. However, like all landing forces they experienced heavy casualties when faced with determined resistance, such as at the invasion of Timor and the Battle of Milne Bay; this was due to their unwillingness to surrender, when out of ammunition, they would resort to hand-to-hand fighting with their swords and bayonets. To combat defended positions in the Pacific, the Landing Forces created new tactics and techniques, that would be adopted by the Allies in their sea-borne invasions. In a well known last stand in 1943, 2,619 men of the 7th Sasebo SNLF and 2,000 base personnel at the Battle of Tarawa accounted for over 3,000 U. S. Marine Corps casualties. Kure Naval Base 1st Kure SNLF-At Hainan Naval District, 3rd China Fleet 2nd Kure SNLF 3rd Kure SNLF 5th Kure SNLF 6th Kure SNLF 7th Kure SNLF Maizuru Naval Base 1st Maizuru SNLF 2nd Maizuru SNLF 4th Maizuru SNLF 5th Maizuru SNLF Sasebo Naval Base 1st Sasebo SNLF 2nd Sasebo SNLF-Under 32nd Special Base Force, 3rd Fleet 5th Sasebo SNLF 6th Sasebo SNLF 7th Sasebo SNLF 8th Sasebo SNLF Shanghai Naval Base Sasebo Combined SNLF Yokosuka Naval Base 1st Yokosuka SNLF 2nd Yokosuka SNLF 3rd Yokosuka SNLF 4th Yokosuka SNLF 5th Yokosuka SNLF 6th Yokosuka SNLF 7th Yokosuka SNLF Ryojun SNLF: special naval guard detached in Ryojun port, Kwantung belonged in Ryojun Guard District.
Shanghai SNLF: special naval guard based in Shanghai port, China belonged in China Theater Fleet. Merged into Canton Special Base Force based in Guangzhou area. Yangtze SNLF: special river squadron detached along the Yangtze river area inside of 1st China Fleet. Hankow SNLF: special naval guard based in Hankow and Wuchang ports,belonged to Middle River Division,inside Yangtze River Fleet and 1st China Fleet. Canton SNLF: special naval guard detached in Guangzhou port, Kwangtung belonged inside of Canton Special Base Force. See article:Japanese marine paratroopers of World War II Yokosuka Naval Base 1st Yokosuka SNLF the 1st was disbanded after its operations in Celebes were completed. 3rd Yokosuka SNLF Made a drop on Timor. Taken into the 1st Yokosuka SNLF. See article:Imperial Japanese Navy Armor Units Shanghai SNLF Tank Company Milne Tank Platoon of Kure 5th SNLF Tarawa Tank Unit of Sasebo 7th SNLF Kwajalein Armor Unit of Sasebo 7th SNLF Navy tank unit of 55th Guard Unit,Yokosuka 1st SNLF Itoh Armored Detachment SNLF Makin Armor SNLF Detachment of Navy 3rd Special Base Force SNLF infantry training centers: Located in main bases of Kure, Sasebo, Yokosuka along special training centers of Ryojun and Dairen in Kantogun.
SNLF paratrooper school: Recruits were trained at the army/navy paratrooper training base on Kanto Plain. SNLF land armor school: Created in the Tateyama IJN Ordnance School, across from Tokyo on the Boso Peninsula. SNLF amphibious armor school: Was established in the IJN aquatic armour unit at Q-Base on Nasakejima in 1943 and the first trained units were sent to Rabaul and the Marshall Islands in October of same year. On board ship the sailors of the SNLF wore their standard IJN blue or white uniforms but when on land the SNLF wore a uniform similar to that of the Imperial Japanese
Rising Sun Flag
The Rising Sun Flag was used by feudal warlords in Japan during the Edo period. On May 15, 1870, as a policy of the Meiji government, it was adopted as the war flag of the Imperial Japanese Army, on October 7, 1889, it was adopted as the naval ensign of the Imperial Japanese Navy, it is still used in Japan as a symbol of tradition and good fortune, is incorporated into commercial products and advertisements. The flag is flown by the Japan Maritime Self-Defense Force and a modified version is flown by the Japan Self-Defense Forces and the Japan Ground Self-Defense Force; the flag of Japan and the rising sun had symbolic meaning since the early 7th century in the Asuka period. The Japanese archipelago is east of the Asian mainland, is thus where the sun "rises". In 607 CE, an official correspondence that began with "from the Emperor of the rising sun" was sent to Chinese Emperor Yang of Sui. Japan is referred to as "the land of the rising sun". In the 12th-century work, The Tale of the Heike, it was written that different samurai carried drawings of the sun on their fans.
A well-known variant of the flag of Japan sun disc design is the sun disc with 16 red rays in a Siemens star formation. The Rising Sun Flag has been used as a traditional national symbol of Japan since the Edo period, it is featured in antique artwork such as ukiyo-e prints through history. Such as the "Lucky Gods' visit to Enoshima", ukiyo-e print by Utagawa Yoshiiku in 1869 and "One Hundred Views of Osaka, Three Great Bridges", ukiyo-e print by Utagawa Kunikazu in 1854; the Fujiyama Tea Co. used it as a wooden box label of Japanese tea for export in the Meiji period / Taisho period. The Japanese word for Japan is 日本, pronounced Nihon or Nippon and means "the origin of the sun"; the character nichi means "sun" or "day". The compound therefore means "origin of the sun" and is the source of the popular Western epithet "Land of the Rising Sun"; the red disc symbolizes the red lines are light rays shining from the rising sun. It was used by the daimyō and Japan's military the Imperial Japanese Army and the Imperial Japanese Navy.
The ensign, known in Japanese as the Jyūrokujō-Kyokujitsu-ki, was first adopted as the war flag on May 15, 1870, was used until the end of World War II in 1945. It was re-adopted on June 30, 1954, is now used by the Japan Maritime Self-Defense Force; the Japan Self-Defense Forces and Japan Ground Self-Defense Force use a variation of the Rising Sun Flag with red and gold colors. The Rising Sun Flag has been used as a traditional national symbol of Japan since at least the Edo period, it has been used in many ukiyo-e prints through history. For example the "Lucky Gods' visit to Enoshima", ukiyo-e print by Utagawa Yoshiiku in 1869 and "One Hundred Views of Osaka, Three Great Bridges", ukiyo-e print by Utagawa Kunikazu in 1854; the Fujiyama Tea Co. used it as a wooden box label of Japanese tea for export in the Meiji period / Taisho period. The design is similar to the flag of Japan; the difference compared to the flag of Japan is that the Rising Sun Flag has extra sun rays exemplifying the name of Japan as "The Land of the Rising Sun".
The Imperial Japanese Army first adopted the Rising Sun Flag in 1870. The Imperial Japanese Army and the Imperial Japanese Navy both had a version of the flag; the flag was used until Japan's surrender in World War II during August 1945. After the establishment of the Japan Self-Defense Forces in 1954, the flag was re-adopted and approved by the GHQ/SCAP; the flag with 16 rays is today the ensign of the Maritime Self-Defense Force while the Ground Self-Defense Force uses an 8-ray version. Commercially the Rising Sun Flag is used on many products, clothing, beer cans, bands, comics, movies, video games, etc; the Rising Sun Flag appears on commercial product labels, such as on the cans of one variety of Asahi Breweries lager beer. The design is incorporated into the logo of the Japanese newspaper Asahi Shimbun. Among fishermen, the tairyō-ki represents their hope for a good catch of fish. Today it is used as a decorative flag on vessels as well as for events; the Rising Sun Flag is used at sporting events by the supporters of Japanese teams and individual athletes as well as by non-Japanese.
The Rising Sun Flag is the war flag and naval ensign of the Japan Maritime Self-Defense Force since June 30, 1954. JSDF Chief of Staff Katsutoshi Kawano said the Rising Sun Flag is the Maritime Self-Defense Force sailors' "pride"; the Japan Self-Defense Forces and the Japan Ground Self-Defense Force use the Rising Sun Flag with eight red rays extending outward, called Hachijō-Kyokujitsuki. A gold border lies around the edge; the flag is used by non-Japanese, for example, in the emblems of some U. S. military units based in Japan, by the American blues rock band Hot Tuna, on the cover of its album Live in Japan. It is used as an emblem of the United States Fleet Activities Sasebo, as a patch of the Strike Fighter Squadron 94, a mural at Misawa Air Base, the former insignia of Strike Fighter Squadron 192 and Joint Helmet Mounted Cueing System with patches of the 14th Fighter Squadron; some ex
Imperial Japanese Army
The Imperial Japanese Army was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor of Japan as supreme commander of the army and the navy. An Inspectorate General of Aviation became the third agency with oversight of the army. During wartime or national emergencies, the nominal command functions of the emperor would be centralized in an Imperial General Headquarters, an ad-hoc body consisting of the chief and vice chief of the Army General Staff, the Minister of the Army, the chief and vice chief of the Naval General Staff, the Inspector General of Aviation, the Inspector General of Military Training. In the mid-19th century, Japan had no unified national army and the country was made up of feudal domains with the Tokugawa shogunate in overall control, which had ruled Japan since 1603; the bakufu army, although large force, was only one among others, bakufu efforts to control the nation depended upon the cooperation of its vassals' armies.
The opening of the country after two centuries of seclusion subsequently led to the Meiji Restoration and the Boshin War in 1868. The domains of Satsuma and Chōshū came to dominate the coalition against the shogunate. On 27 January 1868, tensions between the shogunate and imperial sides came to a head when Tokugawa Yoshinobu marched on Kyoto, accompanied by a 15,000-strong force consisting of troops, trained by French military advisers, they were opposed by 5,000 troops from the Satsuma, Chōshū, Tosa domains. At the two road junctions of Toba and Fushimi just south of Kyoto, the two forces clashed. On the second day, an Imperial banner was given to the defending troops and a relative of the Emperor, Ninnajinomiya Yoshiaki, was named nominal commander in chief, in effect making the pro-imperial forces an Imperial army; the bafuku forces retreated to Osaka, with the remaining forces ordered to retreat to Edo. Yoshinobu and his closest advisors left for Edo by ship; the encounter at Toba–Fushimi between the imperial and shogunate forces marked the beginning of the conflict.
With the court in Kyoto behind the Satsuma-Chōshū-Tosa coalition, other domains that were sympathetic to the cause—such as Tottori and Hizen —emerged to take a more active role in military operations. Western domains that had either supported the shogunate or remained neutral quickly announced their support of the restoration movement; the nascent Meiji state required a new military command for its operations against the shogunate. In 1868, the "Imperial Army" being just a loose amalgam of domain armies, the government created four military divisions: the Tōkaidō, Tōsandō, San'indō, Hokurikudō, each of, named for a major highway. Overseeing these four armies was a new high command, the Eastern Expeditionary High Command, whose nominal head was prince Arisugawa-no-miya, with two court nobles as senior staff officers; this connected the loose assembly of domain forces with the imperial court, the only national institution in a still unformed nation-state. The army continually emphasized its link with the imperial court: firstly.
To supply food and other supplies for the campaign, the imperial government established logistical relay stations along three major highways. These small depots held stockpiled material supplied by local pro-government domains, or confiscated from the bafuku and others opposing the imperial government. Local villagers were impressed as porters to move and deliver supplies between the depots and frontline units; the new army fought under makeshift arrangements, with unclear channels of command and control and no reliable recruiting base. Although fighting for the imperial cause, many of the units were loyal to their domains rather than the imperial court. In March 1869, the imperial government created various administrative offices, including a military branch; the imperial court told the domains to restrict the size of their local armies and to contribute to funding a national officers' training school in Kyoto. However, within a few months the government disbanded both the military branch and the imperial bodyguard: the former was ineffective while the latter lacked modern weaponry and equipment.
To replace them, two new organizations were created. One was the military affairs directorate, composed of two bureaus, one for the army and one for the navy; the directorate drafted an army from troop contributions from each domain proportional to each domain's annual rice production. This conscript army integrated samurai and commoners from various domains into its ranks; as the war continued, the military affairs directorate expected to raise troops from the wealthier domains and, in June, the organization of the army was fixed, where each domain was required to send ten men for each 10,000 koku of rice produced. However, this policy put the imperial government in direct competition with the domains for military recruitment, not rectified until April 1868, when the government banned the domains from enlisting troops; the quota system never worked as intended an
Anti-aircraft warfare or counter-air defence is defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action". They include surface based and air-based weapon systems, associated sensor systems and control arrangements and passive measures, it may be used to protect naval and air forces in any location. However, for most countries the main effort has tended to be'homeland defence'. NATO refers to airborne naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence as are initiatives to adapt air defence to the task of intercepting any projectile in flight. In some countries, such as Britain and Germany during the Second World War, the Soviet Union, NATO, the United States, ground-based air defence and air defence aircraft have been under integrated command and control. However, while overall air defence may be for homeland defence including military facilities, forces in the field, wherever they are, invariably deploy their own air defence capability if there is an air threat.
A surface-based air defence capability can be deployed offensively to deny the use of airspace to an opponent. Until the 1950s, guns firing ballistic munitions ranging from 7.62 mm to 152.4 mm were the standard weapons. The term air defence was first used by Britain when Air Defence of Great Britain was created as a Royal Air Force command in 1925. However, arrangements in the UK were called'anti-aircraft', abbreviated as AA, a term that remained in general use into the 1950s. After the First World War it was sometimes prefixed by'Light' or'Heavy' to classify a type of gun or unit. Nicknames for anti-aircraft guns include AA, AAA or triple-A, an abbreviation of anti-aircraft artillery. NATO defines anti-aircraft warfare as "measures taken to defend a maritime force against attacks by airborne weapons launched from aircraft, ships and land-based sites". In some armies the term All-Arms Air Defence is used for air defence by nonspecialist troops. Other terms from the late 20th century include GBAD with related terms SHORAD and MANPADS.
Anti-aircraft missiles are variously called surface-to-air missile and pronounced "SAM" and Surface to Air Guided Weapon. Non-English terms for air defence include the German FlaK, whence English flak, the Russian term Protivovozdushnaya oborona, a literal translation of "anti-air defence", abbreviated as PVO. In Russian the AA systems are called zenitnye systems. In French, air defence is called DCA; the maximum distance at which a gun or missile can engage an aircraft is an important figure. However, many different definitions are used but unless the same definition is used, performance of different guns or missiles cannot be compared. For AA guns only the ascending part of the trajectory can be usefully used. One term is "ceiling", the maximum ceiling being the height a projectile would reach if fired vertically, not useful in itself as few AA guns are able to fire vertically, maximum fuse duration may be too short, but useful as a standard to compare different weapons; the British adopted "effective ceiling", meaning the altitude at which a gun could deliver a series of shells against a moving target.
By the late 1930s the British definition was "that height at which a directly approaching target at 400 mph can be engaged for 20 seconds before the gun reaches 70 degrees elevation". However, effective ceiling for heavy AA guns was affected by nonballistic factors: The maximum running time of the fuse, this set the maximum usable time of flight; the capability of fire control instruments to determine target height at long range. The precision of the cyclic rate of fire, the fuse length had to be calculated and set for where the target would be at the time of flight after firing, to do this meant knowing when the round would fire; the essence of air defence is to destroy them. The critical issue is to hit a target moving in three-dimensional space; this means that projectiles either have to be guided to hit the target, or aimed at the predicted position of the target at the time the projectile reaches it, taking into account speed and direction of both the target and the projectile. Throughout the 20th century, air defence was one of the fastest-evolving areas of military technology, responding to the evolution of aircraft and exploiting various enabling technologies radar, guided missiles and computing (initially electromechanical analogue computing from the 1930s on, as with equipment describ
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1868 until 1945, when it was dissolved following Japan's surrender in World War II. The Japan Maritime Self-Defense Force was formed after the dissolution of the IJN; the Imperial Japanese Navy was the third largest navy in the world by 1920, behind the Royal Navy and the United States Navy. It was supported by the Imperial Japanese Navy Air Service for aircraft and airstrike operation from the fleet, it was the primary opponent of the Western Allies in the Pacific War. The origins of the Imperial Japanese Navy go back to early interactions with nations on the Asian continent, beginning in the early medieval period and reaching a peak of activity during the 16th and 17th centuries at a time of cultural exchange with European powers during the Age of Discovery. After two centuries of stagnation during the country's ensuing seclusion policy under the shōgun of the Edo period, Japan's navy was comparatively backward when the country was forced open to trade by American intervention in 1854.
This led to the Meiji Restoration. Accompanying the re-ascendance of the Emperor came a period of frantic modernization and industrialization; the navy had several successes, sometimes against much more powerful enemies such as in the Sino-Japanese War and the Russo-Japanese War, before being destroyed in World War II. Japan has a long history of naval interaction with the Asian continent, involving transportation of troops between Korea and Japan, starting at least with the beginning of the Kofun period in the 3rd century. Following the attempts at Mongol invasions of Japan by Kubilai Khan in 1274 and 1281, Japanese wakō became active in plundering the coast of China. Japan undertook major naval building efforts in the 16th century, during the Warring States period, when feudal rulers vying for supremacy built vast coastal navies of several hundred ships. Around that time Japan may have developed one of the first ironclad warships when Oda Nobunaga, a daimyō, had six iron-covered Oatakebune made in 1576.
In 1588 Toyotomi Hideyoshi issued a ban on Wakō piracy. Japan built her first large ocean-going warships in the beginning of the 17th century, following contacts with the Western nations during the Nanban trade period. In 1613, the daimyō of Sendai, in agreement with the Tokugawa Bakufu, built Date Maru, a 500-ton galleon-type ship that transported the Japanese embassy of Hasekura Tsunenaga to the Americas, which continued to Europe. From 1604 the Bakufu commissioned about 350 Red seal ships armed and incorporating some Western technologies for Southeast Asian trade. For more than 200 years, beginning in the 1640s, the Japanese policy of seclusion forbade contacts with the outside world and prohibited the construction of ocean-going ships on pain of death. Contacts were maintained, with the Dutch through the port of Nagasaki, the Chinese through Nagasaki and the Ryukyus and Korea through intermediaries with Tsushima; the study of Western sciences, called "rangaku" through the Dutch enclave of Dejima in Nagasaki led to the transfer of knowledge related to the Western technological and scientific revolution which allowed Japan to remain aware of naval sciences, such as cartography and mechanical sciences.
Seclusion, led to loss of any naval and maritime traditions the nation possessed. Apart from Dutch trade ships no other Western vessels were allowed to enter Japanese ports. A notable exception was during the Napoleonic wars. Frictions with foreign ships, started from the beginning of the 19th century; the Nagasaki Harbour Incident involving HMS Phaeton in 1808, other subsequent incidents in the following decades, led the shogunate to enact an Edict to Repel Foreign Vessels. Western ships, which were increasing their presence around Japan due to whaling and the trade with China, began to challenge the seclusion policy; the Morrison Incident in 1837 and news of China's defeat during the Opium War led the shogunate to repeal the law to execute foreigners, instead to adopt the Order for the Provision of Firewood and Water. The shogunate began to strengthen the nation's coastal defenses. Many Japanese realized that traditional ways would not be sufficient to repel further intrusions, western knowledge was utilized through the Dutch at Dejima to reinforce Japan's capability to repel the foreigners.
Numerous attempts to open Japan ended in failure, in part to Japanese resistance, until the early 1850s. During 1853 and 1854, American warships under the command of Commodore Matthew Perry entered Edo Bay and made demonstrations of force requesting trade negotiations. After two hundred years of seclusion, the 1854 Convention of Kanagawa led to the opening of Japan to international trade and interaction; this was soon followed by treaties with other powers. As soon as Japan opened up to foreign influences, the Tokugawa shogunate recognized the vulnerability of the country from the sea and initiated an active policy of assimilation and adoption of Western naval technologies. In 1855, with Dutch assistance, the shogunate acquired its first steam warship, Kankō Maru, began using it for training, establishing a Naval Training Center at Nagasaki. Samurai such as the future Admiral Enomoto Takeaki were sent by the shogunate to study in the Netherlands for several years. In 1859 the