Part II The Basics of Japan’s Defense Policy and Build-up of Defense Capability
Chapter 1 The Basic Concepts of Japan’s Defense Policy and Related Issues
Section 1. Measures to Ensure Japan’s Security
Peace and safety are vital to ensuring that people can live without fear and so that Japan can continue to
develop and prosper. In addition, national independence must be protected in order to allow Japan to
individually determine how its politics, economy, and society should be, and maintain its culture, tradition,
and values. Peace, safety, and independence cannot be secured by wishing alone. Indeed, these can only
be secured by comprehensively implementing various measures in consideration of the current situation
of the increasingly interdependent international community, including for Japan’s own defense
capabilities, diplomatic efforts, and cooperation between allied nations and the international community.
Dependence on foreign trade for resources and food is particularly high, and maintaining peace and
cooperation in the international community is of tremendous importance to Japan, as it places the
foundation for its development and prosperity on free trade. For this reason, Japan is working to
strengthen bilateral cooperative relationships such as the Japan–U.S. alliance1 while actively advancing
regional cooperation in the Asia-Pacific region and with the United Nations, and to prevent and resolve
conflicts and disputes, develop economically, promote arms control and disarmament, ensure maritime
security, and enhance mutual understanding and trust. Domestically Japan also works to enrich the
backbone of the people, which is characterized by ensuring stable lifestyles for the people and protecting
the country, while also working to establish a security foundation by implementing various measures in
such sectors as the economy and education so as not to allow for openings that would invite an invasion.
Meanwhile, the reality of the current international community suggests that it is not necessarily possible
to prevent invasions from the outside via nonmilitary means alone, and in the event that Japan was
invaded it would not be able to remove said threat. Defense capabilities are Japan’s ultimate guarantee for
security, expressing the will and capacity of Japan to defend against foreign invasions. In this way, the
function of defense capabilities cannot be substituted by any other method.
For this reason, defense capabilities are vital for ensuring an appropriate response to various
contingencies arising from the security challenges and destabilizing factors, which are diverse, complex,
and intertwined, as outlined in Part I. Moreover, from the perspective of improving the security
environment surrounding Japan and preventing threats to our country from emerging, importance is
growing for the role played by defense capabilities in areas such as cooperation in the Asia-Pacific region
and working together as a member of the international community.
In consideration of the factors above, Japan is advancing the development of a proper level of defense
capabilities. The security of Japan is ensured through such individual efforts to develop adequate defense
capabilities along with Japan–U.S. Security Arrangements to formulate watertight defense measures.
Japan recognizes the important role played by its defense capabilities and works in a variety of fields to
ensure national security while also aiming to create peace and safety for the Asia-Pacific region and
consequently the entire world.
(See Part III, Chapter 2, Section 2)
Section 2. The Constitution and the Right of Self-Defense
1. The Constitution and the Right of Self-Defense
Since the end of World War II, Japan has worked hard to build a peace-loving nation far from the miseries
of war. The Japanese people desire lasting peace, and the principle of pacifism is enshrined in the
Constitution, of which Article 9 renounces war, the possession of war potential, and the right of
belligerency by the state. Nonetheless, since Japan is an independent nation, these provisions do not deny
Japan’s inherent right of self-defense as a sovereign state.
Since the right of self-defense is not denied, the Government interprets this to mean that the Constitution
allows Japan to possess the minimum level of armed force needed to exercise that right. Therefore, the
Government, as part of its exclusively national defense-oriented policy under the Constitution, maintains
the Self-Defense Forces (SDF) as an armed organization, and continues to keep it equipped and ready for
operations.
2. The Government’s View on Article 9 of the Constitution
1. The Permitted Self-Defense Capability
Under the Constitution, Japan is permitted to possess the minimum necessary level of self-defense
capability.
The specific limit may vary with the prevailing international situation, the technologies available, and
various other factors, and it is discussed and decided according to annual budgets and other factors by the
Diet on behalf of the people. Whether such capability constitutes a “war potential” that is prohibited by
Article 9, Paragraph 2 of the Constitution must be considered within the context of Japan’s overall
military strength. Therefore, whether the SDF should be allowed to possess certain armaments depends
on whether such possession would cause its total military strength to exceed the constitutional limit.
The possession of armaments deemed to be offensive weapons designed to be used only for the mass
destruction of another country, which would, by definition, exceed the minimum necessary level, is not
permissible under any circumstances. For example, the SDF is not allowed to possess intercontinental
ballistic missiles (ICBM), long-range strategic bombers, or attack aircraft carriers.
2. Requirements for Exercising the Right of Self-Defense
The Government interprets Article 9 of the Constitution to mean that armed force can be used to exercise
the right of self-defense only when the following three conditions are met:
1) When there is an imminent and illegitimate act of aggression against Japan;
2) When there is no appropriate means to deal with such aggression other than by resorting to the right of
self-defense;
and
3) When the use of armed force is confined to the minimum necessary level.
3. Geographic Boundaries within which the Right of Self-Defense may be Exercised
The use of minimum necessary force to defend Japan under the right of self-defense is not necessarily
confined to the geographic boundaries of Japanese territory, territorial waters and airspace. However, it is
difficult to give a general definition of the actual extent to which it may be used, as this would vary with
the situation.
Nevertheless, the Government interprets that the Constitution does not permit armed troops to be
dispatched to the land, sea, or airspace of other countries with the aim of using force; such overseas
deployment of troops would exceed the definition of the minimum necessary level for self-defense.
4. The Right of Collective Self-Defense
International law permits a state to have the right of collective self-defense, which is the right to use force
to stop an armed attack on a foreign country with which the state has close relations, even if the state
itself is not under direct attack. Since Japan is a sovereign state, it naturally has the right of collective
self-defense under international law. Nevertheless, the Japanese Government believes that the exercise of
the right of collective self-defense exceeds the minimum necessary level of self-defense authorized under
Article 9 of the Constitution and is not permissible.
5. The Right of Belligerency
Article 9, Paragraph 2 of the Constitution prescribes that “the right of belligerency of the state will not be
recognized”. However, the “right of belligerency” does not mean the right to engage in battle; rather it is a
general term for various rights that a belligerent nation has under international law, including the
authority to inflict casualties and damage upon the enemy’s military force and to occupy enemy territory.
On the other hand, Japan may of course use the minimum level of force necessary to defend itself. For
example, if Japan inflicts casualties and damage upon the enemy’s military force in exercising its right of
self-defense, this is conceptually distinguished from the exercise of the right of belligerency, even though
those actions do not appear to be different. Occupation of enemy territory, however, would exceed the
minimum necessary level of self-defense and so is not permissible.
Section 3. The Basis of Defense Policy
1. Basic Policy for National Defense
Under the Constitution, Japan has adhered to its Basic Policy for National Defense2, which was adopted
by the National Defense Council and approved by the Cabinet in 1957.
The national defense objectives provided in the Basic Policy for National Defense are to prevent direct
and indirect invasions of Japan, eliminate threats for the remote chance that Japan is invaded, and thus
protect the independence and peace of Japan as a democratic nation. In addition, the Basic Policy lays
down the following four items as a basic policy for achieving these objectives.
1) Support the activities of the United Nations, cooperate with other nations, and aim to achieve world
peace.
2) Establish the foundation necessary to ensure a stable quality of life for the people, boost nationalism,
and guarantee the nation’s safety.
3) Progressively develop efficient national defense capabilities to the necessary limit for self-defense in
accordance with national power and circumstances.
4) Deal with foreign invasions of Japan based on security arrangements formed with the United States
until the United Nations becomes able to effectively prevent said threats.
(See Reference 6 Basic Policy for National Defense)
2. Other Basic Policies
Under the Basic Policy for National Defense, Japan has been building a modest defense capability under
the Constitution purely for exclusively defense-oriented purposes without becoming a military power that
could threaten other countries, while adhering to the principle of civilian control of the military, observing
the Three Non-Nuclear Principles, and firmly maintaining the Japan–U.S. Security Arrangements.
1. Exclusively Defense-Oriented Policy
The exclusively defense-oriented policy means that Japan will not employ defensive force unless and
until an armed attack is mounted on Japan by another country, and even in such a case, only the minimum
force necessary to defend itself may be used. Furthermore, only the minimum defense forces necessary
for self-defense should be retained and used. This exclusively defense-oriented policy is a passive defense
strategy that is consistent with the spirit of the Constitution.
2. Not Becoming a Military Power
There is no established definition for the term “military power”. For Japan, however, not becoming a
military power that could threaten the security of other countries means that Japan will not possess more
military force than is necessary for self-defense and that could pose a threat to other countries.
3. The Three Non-Nuclear Principles
The Three Non-Nuclear Principles are that Japan: will not possess nuclear weapons, will not produce
nuclear weapons, and will not allow nuclear weapons into Japan. Japan adheres to the Three Non-Nuclear
Principles as a fixed national policy.
Japan is prohibited from manufacturing or possessing nuclear weapons also under the Atomic Energy
Basic Law3. In addition, Japan ratified the Treaty on the Non-Proliferation of Nuclear Weapons (NPT),
and as a non-nuclear weapons state, is not permitted to produce or acquire nuclear weapons 4.
4. Ensuring Securing Civilian Control
Civilian control of the military means the precedence of political will over the military in a democratic
state, and hence or in other words, democratic political control over the military.
Learning lessons from World War II, Japan has adopted the following strict system of uncompromising
civilian control system that is entirely different from those under the former Constitution5. Civilian
control ensures that the SDF is maintained and operated in accordance with the will of the people.
The Japanese people are represented in by the Diet, which makes legislative and budgetary decisions on
matters such as the authorized number of uniformed SDF personnel and principal institutions of the
MOD/SDF. The Diet It also approves issuance of Defense Operation Ordersdefense operations.
As part of its general administrative functions, the Cabinet has entire authority over issues related to
defense. The Constitution requires the Prime Minister and other Ministers of State in the Cabinet to be
civilians. The Prime Minister, acting on behalf of the Cabinet, is the supreme commander
commander-in-chief of the SDF. The Minister of Defense, who is exclusively in charge of national
defense, exercises general control over SDF activities. In addition, the Security Council of Japan6 within
the Cabinet discusses important defense matters deliberates important national defense-related matters.
At Within the Ministry of Defense, the Minister of Defense is in charge of administrative work related to
national defense and controls the SDF. The Minister of Defense is assisted in planning policies by the
Senior Vice-Minister and two Parliamentary Secretaries7.
In addition, in relation to important affairs under the jurisdiction of the Ministry of Defense, special
advisors to the Ministry Minister of Defense are in place to fulfill such functions as offering advice to the
Minister of Defense based on their own insight knowledge and experience, while the Defense Council
draws together the political appointees, civil servants and uniformed SDF personnel of the Ministry of
Defense to deliberate on important policies under the ministry’s jurisdiction. In this way, the Ministry of
Defense aims to further enhance the civilian control system.
See Part III, Chapter 4, Section1（pxx）
As mentioned above, the civilian control systems are well-established. The success of the system depends
on ongoing political and administrative efforts, as well as a keen interest among Japanese citizens in
defense issues.
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In general, this refers to the relationship, based on the Japan-U.S. Security System, whereby both
nations, as countries sharing fundamental values and interests, coordinate and cooperate closely in a
range of areas in security, politics and economics. See Part III, Chapter 2, Section 2.
The function of this Council was taken over by the Security Council of Japan in 1986.
Article 2 of the Atomic Energy Basic Law states that “The research, development and utilization of
atomic energy shall be limited to peaceful purposes, aimed at ensuring safety and performed
independently under democratic management.”
Article 2 of the NPT states that “Each non-nuclear weapon State Party to the Treaty undertakes....not to
manufacture or otherwise acquire nuclear weapons or other nuclear explosive devices...”
The Cabinet’s control over military matters was limited.
Members of the Security Council are the Prime Minister (chairman); Minister designated pursuant to
Article 9 of the Cabinet Law (Minister of State pre-designated to perform duties of the Prime Minister
temporarily when the Prime Minister is absent, involved in an accident, or in a similar situation);
Minister of Internal Affairs and Communications; Minister for Foreign Affairs; Minister of Finance;
Minister of Economy, Trade and Industry; Minister of Land, Infrastructure, Transport and Tourism;
Minister of Defense; the Chief Cabinet Secretary; and Chairperson of the National Public Safety
Commission.
In addition, to help the Minister of Defense effectively handle administrative work related to national
defense and to reliably manage the SDF, other systems to assist the Minister have been established. See
Part III, Chapter 4, Section 1 for the organization of the SDF, including such advisory systems to the
Minister.