The are the military forces of Japan. The JSDF comprises the Japan Ground Self-Defense Force, the Japan Maritime Self-Defense Force, and the Japan Air Self-Defense Force. They are controlled by the Ministry of Defense with the prime minister as commander-in-chief.
Since the end of the Cold War, and particularly into the 21st century, increased tensions with China, North Korea, and Russia have reignited debate over the status of the JSDF and their relationship to Japanese society. The JSDF have maintained a close alliance with the United States, and have prioritized greater cooperation and partnership with Australia, India, Taiwan, South Korea, Singapore, the United Kingdom, and NATO, as well as acquiring new equipment and hardware.
Japan surrendered to the Allied Powers on 15 August 1945, and officially exchanged instruments of surrender in Tokyo Bay on 2 September, after which Japan underwent a U.S.-led military occupation for seven years, until 28 April 1952. The Occupation was commanded by American general Douglas MacArthur, whose office was designated the Supreme Command for the Allied Powers (SCAP). In the initial phase of the occupation, from 1945 to 1946, SCAP had pursued an ambitious program of social and political reform, designed to ensure that Japan would never again be a threat to world peace.
Among other reforms, SCAP worked with Japanese leaders to completely disband the Japanese military. In addition, SCAP sought to unravel the wartime Japanese police state by breaking up the national police force into small American-style police forces controlled at the local level. SCAP also sought to empower previously marginalized groups that it believed would have a moderating effect on future militarism, legalizing the Communist and Socialist parties and encouraging the formation of labor unions. The crowning achievement of the first phase of the occupation was the promulgation at SCAP's behest in 1947 of a new Constitution of Japan. Article 9 of the Japanese Constitution explicitly disavows war as an instrument of state policy and promises that Japan will never maintain a military as well as other war potential.
By this time, Cold War tensions were already ramping up in Europe, where the Soviet occupation of Eastern European countries led Winston Churchill to give his 1946 "Iron Curtain" speech, as well as in Asia, where the tide was turning in favor of the Communists in the Chinese Civil War. These shifts in the geopolitical environment led to a profound shift in U.S. government and Allied Occupation thinking about Japan, and rather than focusing on punishing and weakening Japan for its wartime transgressions, the focus shifted to rebuilding and strengthening Japan as a potential ally in the emerging global Cold War, leading to a reversal of many earlier Occupation policies that has come to be known as the "Reverse Course". As part of this shift, MacArthur and other U.S. leaders began to question the wisdom of having insisted upon Japan renouncing all military capabilities. These sentiments were intensified in 1950 as Occupation troops began to be moved to the Korean War (1950âÂÂ1953) theater. This left Japan defenseless and vulnerable, and caused U.S. and Japanese conservative leaders alike to becoming increasingly aware of a pressing need to enter a mutual defense relationship with the United States in order to guarantee Japan's external security in the absence of a Japanese military. Meanwhile, on the Japanese domestic front, rampant inflation, continuing hunger and poverty, and the rapid expansion of leftist parties and labor unions led Occupation authorities to fear that Japan was ripe for communist exploitation or even a communist revolution and to believe that conservative and anti-communist forces in Japan needed to be strengthened. Accordingly, in July 1950, Occupation authorities authorized the establishment of a , consisting of 75,000 men equipped with light infantry weapons. In 1952, the , the waterborne counterpart of NPR, was also founded.
The Security Treaty Between the United States and Japan was signed on 8 September 1951 and came into force on 28 April 1952. While the treaty allowed the United States to maintain military bases in Japan, it did not obligate US forces to defend Japan should Japan come under attack. As left-wing protests in Japan remained a major concern to Japanese and American leaders alike, the treaty explicitly allowed US military forces based in Japan to put down "internal riots and disturbances" in Japan. In addition, in mid-1952, the National Police Reserve was expanded to 110,000 men and named the "National Safety Forces". Along with it, the Coastal Safety Force was moved to the National Safety Agency to start a de facto navy.
Meanwhile, the Japanese government began a long and ongoing process of gradually reinterpreting Article 9 of the Japanese Constitution to allow greater and greater military capabilities, under the interpretation that Article 9 disallowed offensive warmaking capabilities but did not necessarily deny the nation the inherent right to self-defense. These reinterpretations were avidly encouraged by the government of United States, which hoped that by remilitarizing Japan would be able to take up more of the burden for its own self-defense. This reinterpretation of Article 9 cleared the way for the creation of a Defense Agency and the transformation of the National Security Force into a "Self-Defense Force" that would be a military in all but name.
On 1 July 1954, the National Security Board was reorganized as the Defense Agency, and the National Security Force was reorganized afterwards as the Japan Ground Self-Defense Force (de facto post-war Japanese Army), the Coastal Safety Force was reorganized as the Japan Maritime Self-Defense Force (de facto post-war Japanese Navy), and the Japan Air Self-Defense Force (de facto post-war Japanese Air Force) was established as a new branch of JSDF. General Keizà  Hayashi was appointed the first chairman of the Joint Staff CouncilâÂÂprofessional head of the three branches. The enabling legislation for this was the 1954 (Act No. 165 of 1954).
The Far East Air Force, U.S. Air Force, announced on 6 January 1955 that 85 aircraft would be turned over to the fledgling Japanese air force on about 15 January, the first equipment of the new force.
On 19 January 1960, the United States and Japan signed a revised version of the US-Japan Security Treaty which corrected the unequal status of Japan in the 1951 treaty by adding mutual defense obligations and which remains in force today. The U.S. is required to give prior notice to Japan of any mobilization of US forces based in Japan. The US is also prohibited from exerting any power on domestic issues within Japan. The treaty obligates Japan and the United States to assist each other if there is an armed attack in territories administered by Japan. Because it states that any attack against Japan or the United States in Japanese territory would be dangerous to each country's peace and safety, the revised treaty requires Japan and the United States to maintain capacities to resist common armed attacks; thus, it explains the need for US military bases in Japan. This had the effect of establishing a military alliance between Japan and the United States. The revised treaty has never been amended since 1960, and thus has lasted longer in its original form than any other alliance between two great powers since the Peace of Westphalia treaties in 1648.
Although possession of nuclear weapons is not explicitly forbidden in the constitution, Japan does not own any. The Atomic Energy Basic Law of 1956 limits research, development, and use of nuclear power to peaceful uses only. Beginning in 1956, national policy embodied non-nuclear principles that forbade the nation from possessing or manufacturing nuclear weapons or allowing them to be introduced into its territories. In 1976, Japan ratified the Treaty on the Non-Proliferation of Nuclear Weapons (adopted by the United Nations Security Council in 1968) and reiterated its intention never to "develop, use, or allow the transportation of nuclear weapons through its territory"; nonetheless, because of its advanced technological capabilities and large number of operating nuclear power plants, Japan is considered "nuclear capable", i.e., it could develop usable nuclear weapons within one year if the political situation changes significantly. Thus, many analysts consider Japan a de facto nuclear state. Japan is often said to be a "screwdriver's turn" away from possessing nuclear weapons or possessing a "bomb in the basement".
In 1983, Japanese prime minister Yasuhiro Nakasone pledged to make Japan an "unsinkable aircraft carrier in the Pacific", assisting the United States in defending against the threat of Soviet bombers.
In 1990, the United States called on its ally Japan for assistance in the Gulf War. However, then-current Japanese interpretation of Article 9 forbade the overseas dispatch of Japanese military troops. Accordingly, Japan contributed $9 billion in monetary support.
On 28 May 1999, the Regional Affairs Law was enacted. It allows Japan to automatically participate as "rear support" if the United States wages war under "regional affairs".
The Anti-Terrorism Special Measures Law was passed on 29 October 2001. It allows the JSDF to contribute by itself to international efforts to the prevention and eradication of terrorism. While on duty, the JSDF can use weapons to protect itself and others who come under its control. Previously Japan's policy was non-involvement.
In between the Gulf War and the start of the Iraq War in 2003, the Japanese government revised its interpretation of Article 9, and thus during the Iraq War, Japan was able to dispatch noncombat ground forces in a logistical support role in support of U.S. operations in Iraq.
On 27 March 2004, the Japan Defense Agency activated the Special Operations Group with the mandate under the JGSDF as its Counter-terrorist unit.
On 8 June 2006, the Cabinet of Japan endorsed a bill elevating the under the Cabinet Office to full-fledged cabinet-level . This was passed by the National Diet in December 2006 and has been enforced since 9 January 2007.
Section 2 of Article 3 of the Self Defense Forces Act was revised on 9 January 2007. JSDF activities abroad were elevated from "miscellaneous regulations" to "basic duties". This fundamentally changed the nature of the JSDF because its activities were no longer solely defensive. JMSDF ships can be dispatched worldwide such as in activities against pirates. The JSDF's first postwar overseas base was established in Djibouti (July 2010). On 18 September 2015, the National Diet enacted the 2015 Japanese military legislation, a series of laws that allow Japan's Self-Defense Forces to defend allies in combat. The JSDF may provide material support to allies engaged in combat overseas. The new law also allows JSDF troops to defend weapons platforms belonging to Japan's allies if doing so would somehow contribute to Japan's defense. The justification being that not defending or coming to the aid of an ally under attack weakens alliances and endangers Japan. These were Japan's broadest changes to its defense laws since World War II. The JSDF Act was amended in 2015 to make it illegal for JSDF personnel/staff to participate in collective insubordination or to command forces without authority or in violation of orders, which was stated to be the reason Japan was involved in China in World War II. A Credit Suisse survey published in 2015 ranked Japan as the world's fourth most-powerful military behind Russia, China, and United States. Since March 2016, Japan's Legislation for Peace and Security enables seamless responses of the JSDF to any situation to protect the lives and livelihood of Japanese citizens. It also increases proactive contributions to peace and security in the world and deepens cooperation with partners. This enhanced the Japan-US alliance as global partners to promote peace and security in the region and the international community.
Japan activated the Amphibious Rapid Deployment Brigade, its first marine unit since World War II, on 7 April 2018. It is trained to counter invaders from occupying Japanese islands. The Ministry of Defense said that beginning 1 October 2018, the maximum age for enlisted personnel and non-commissioned officer applicants would be raised from 26 to 32 to secure "a stable supply of Self-Defense Forces [military] personnel amid a declining pool of recruits due to the recently declining birth rate". In March 2019, the Ministry of Defense intended to establish its first regional cyber protection unit in the Western Army of the Japan Ground Self-Defense Force (JGSDF) to safeguard defense communications from cyber attacks, such as for personnel deployed on remote islands with no established secure lines. The Ministry of Defense has been developing supersonic glide bombs to strengthen the defense of Japan's remote islands, including the Senkaku Islands. The anti-surface strike capability will be used to help the Amphibious Rapid Deployment Brigade's landing and recapture operations of remote islands.
British troops of the Honourable Artillery Company (HAC) conducted a field exercise together for the first time with Japanese GSDF soldiers in Oyama, Shizuoka prefecture on 2 October 2018. This also marked the first time in history that foreign soldiers other than Americans have had field exercises on Japanese soil. The purpose was to improve their strategic partnership and security cooperation. The JGSDF and the Indian Army conducted their first joint military exercise in the Indian state of Mizoram from 27 October to 18 November 2018, practicing anti-terror drills and improving bilateral cooperation between 60 Japanese and Indian officers. From 29 October to 2 November 2018, Japan and the United States conducted the largest military exercise around Japan to date, known as Keen Sword. It included 57,000 sailors, marines and airmen. Of those, 47,000 service members were from the JSDF and 10,000 from the U.S. Armed Forces. A naval supply ship and frigate of the Royal Canadian Navy also participated. There were simulations of air combat, ballistic missile defense, and amphibious landings.
Japan unveiled the 84-meter long, 2,950-ton , Japan's first submarine powered by lithium-ion batteries, on 4 October 2018. It was developed by Mitsubishi Heavy Industries. The Japan Maritime Self-Defense Force used it for the first time in March 2020.
The Japanese government approved the first-ever JGSDF dispatch to a peacekeeping operation that was not led by the United Nations. Two JGSDF officers monitored a cease-fire between Israel and Egypt at the Multinational Force and Observers command in the Sinai Peninsula from 19 April till 30 November 2019. Defense Minister Takeshi Iwaya announced plans to deploy Type 12 surface-to-ship missiles in March 2020. The missiles have a range of 300 km and would be used to protect the southern Ryukyu Islands. Japan is also developing high-speed gliding missiles with a range of 1000 km.
On 10 September 2020, Japan and India signed a military pact called the Acquisition and Cross-Servicing Agreement (ACSA). The pact enables the exchange of logistical support and supplies. The purpose is to encourage closer cooperation between the two countries and to deter Chinese aggression in Asia. Japan already had such agreements with Australia, Canada, France, UK and USA.
On 5 May 2022, Japan and the United Kingdom signed a defensive partnership which deepens military ties to counter "autocratic, coercive powers" in Europe and the Asia-Pacific region. Prime Ministers Fumio Kishida and Boris Johnson both condemned the Russian invasion of Ukraine.
On 5 May 2022, Japan and the United States signed an agreement. Japanese prime minister Fumio Kishida and U.S. president Joe Biden met together in Tokyo.
Since the post-February 2022 Russian invasion of Ukraine, there has been growing military coordination between China and Russia. This has resulted in an uptick of military activity around Japan.
On 4 August 2022, the Japanese government lodged formal protests to Beijing when five missiles landed near Hateruma in Japan's Exclusive Economic Zone. These Chinese missile launches and military exercises occurred in response to the 2022 visit by Nancy Pelosi to Taiwan.
On 22 October 2022, Japan and Australia signed a new bilateral security agreement that includes military, intelligence and cybersecurity cooperation. It is an upgrade to the 2007 Joint Declaration on Security Cooperation. This is the first time that Japan made such a pact with a country other than the United States.
On 16 December 2022, Japan announced a major policy shift from its exclusively defense-oriented posture by acquiring counterstrike capabilities to hit enemy bases and command-and-control nodes with longer-range standoff missiles and a defense budget increase to 2% of GDP (ÃÂ¥43 trillion, equivalent to approximately US$315 billion