As a country where the Constitution does not allow the organization of an army, the Japan Self-Defense Forces (JSDF) remain one of the best equipped in the region.
Article 9 of Japan’s Constitution states: “Aspiring sincerely to an international peace based on justice and order, the Japanese people forever renounce war as a sovereign right of the nation and the threat or use of force as means of settling international disputes. In order to accomplish the aim of the preceding paragraph, land, sea, and air forces, as well as other war potential, will never be maintained. The right of belligerency of the state will not be recognized.”
However, a part of the Constitution was added, that the country could build and maintain its inherent right to self-defense. Thus, with the security treaty that Japan signed with the United States in 1951, it allows Japan to maintain a garrison in response to external aggression, as well as internal threats and natural disasters.

It started with the National Police Reserve, formed in 1950, consisting of 75,000 men armed with light weapons, then the Coastal Security Force was born two years later. This force was later renamed the Japan Ground Self-Defense Force (JGSDF) and the Maritime Self-Defense Force (JMSDF) on July 1, 1954, while the third force – the Air Self-Defense Force (JASDF) was also established on this date.
Japan’s shift in defense policy is driven in part by China’s rapid military modernization. Chinese coast guard ships regularly appear in the disputed islands between Japan and China. Those changes forced then-Prime Minister Shinzo Abe to amend the self-defense provisions in the country’s constitution. Accordingly, Japan’s defense budget has increased significantly since 2012 after many consecutive years of cuts. Specifically, Japan spent $65 billion on defense in 2020.
Over the past few years, Japanese defense planners have focused on the deployment of military forces. The annual white paper emphasizes this issue, with the goal of protecting the remote islands, specifically the disputed Senkaku Islands between Okinawa and Taiwan (China).
In 2018, the Japan Ground Self-Defense Force’s Rapid Amphibious Deployment Brigade was established. This is a force similar to the US Marines, allowing the military to effectively and quickly conduct defensive operations across the country.
Regarding submarines, Japan, along with Germany, are now considered the world’s two leading manufacturers of diesel and electric powered attack submarines. Tokyo is known for its Soryu and Oyashio classes. With a full-load displacement when submerged up to 4,200 tons, the Soryu has a top speed of about 35 km/h and a range of more than 11,000 km, while achieving extremely low noise levels. The Japan Maritime Self-Defense Force has also commissioned its first non-nuclear submarine, the JS Oryu, powered by a lithium-ion battery for longer and safer underwater operations. This is an important step forward for Japan’s next generation submarine.
After years of using the American P-3 Orion anti-submarine reconnaissance aircraft, Japan developed the Kawasaki P-1 to replace it. Since 2000, Japan has also cooperated with the US to develop the Mitsubishi F-2 fighter as a separate version of the famous F-16 series. Japan is also an important partner in the F-35 stealthy 5th generation fighter project initiated by the US. Up to now, after receiving the F-35, Tokyo is also pursuing a program to develop the Mitsubishi F-3 fighter, equivalent to the F-2 Raptor that the US does not export.
Japan maintains a large Air Defense Identification Zone (ADIZ) around its territory, and its interceptors are regularly tasked with identifying and monitoring intruding foreign military aircraft. Along with the F-15J and F-35 fighters, Japan is also developing a new generation of fighters to replace 87 Mitsubishi F-2A/B multirole fighters.
In October 2018, then-Japanese Defense Minister Takeshi Iwaya announced that the country would purchase nine more E-2Ds, totaling $3.135 billion, to replace the aging E-2C fleet. Earlier, Japan decided to buy 17 more MV-22 Osprey helicopters to supplement the amphibious force being built with the help and effective advice of the US.