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The necessity and possibility for Japan to possess nuclear forces on its own

--The nuclear power balance tilting against the United States and the path to securing a reliable nuclear deterrent --

【日本語版】https://i-rich.org/?p=803

矢野 義昭

Yano Yoshiaki

Senior researcher

International Research Institute for Controversial Histories (iRICH)

June 30, 2022

As we have seen during the recent Russian invasion of Ukraine, it is getting more and more difficult to secure completely the international order, maintained through the U.S. nuclear deterrent power, against attempts to change the status quo.

Guarantee of “nuclear umbrella” for Ukraine was not fulfilled

Ukraine used to own approximately 1,400 nuclear warheads and ranked the third “nuclear power” after Russia and the United States at the time when it became independent from the Soviet Union. However, in 1994, the United States, Britain and Russia, fearing nuclear proliferation from Ukraine, made Ukraine agree to the plan to transfer all its nuclear warheads to Russia on the condition that Ukraine be provided security.

However, after the virtual annexation of Crimea by Russia in 2014, the United States and Britain did not provide protection under their nuclear umbrella for Ukraine’s security as it had been promised. When Ukraine was invaded and threatened with a possible nuclear attack by a nuclear power country, the nuclear umbrella assurance the United States had guaranteed to Ukraine did not work effectively.

As if they anticipated the failure of the “nuclear umbrella” security, China, Russia and the DPRK (North Korea) are strengthening their show of force and nuclear intimidation around Japan.

It is time for us to reexamine the policy of total dependence on the United States with respect to nuclear deterrent, reevaluate the need to keep the Three Non-Nuclear Principles and to seriously discuss the necessity and possibility for Japan to possess its own nuclear deterrent power.

Deterrent power has several levels. The highest level is nuclear weapons and below it come biological and chemical weapons of mass destruction. Under that level, there are conventional, regular weapons. Below weapons level, there are non-military tools, like diplomacy, economics, scientific technology, intelligence and other means of deterrence.

Deterrent will collapse if at any level, one’s power is weaker than that of the opponent. Even if a conflict occurs and escalates, the possession of a more powerful force at a higher level, makes it possible to prevent the conflict from escalating further.

Namely, if a country owns its own nuclear force, theoretically, it can keep the conflict from escalating any further or refuse to accept the plan to end the conflict as the other side wishes, by employing nuclear intimidation at the time when both sides start using regular weapons and the other side is doing better.

The nominal “Three Non-Nuclear Principles” and the lost U.S. “Nuclear Umbrella” reliance

Following the Sato Cabinet decision on October 9, 1972, Japan has been advocating for the “Three Non-Nuclear Principles.” However, the United States itself has kept an ambiguous stance regarding these principles. The U.S. neither denies nor affirms whether the U.S. nuclear submarines carry nuclear weapons. Japanese officials cannot go aboard U.S. submarines passing through the Japanese territorial waters and verify if the submarines carry nuclear weapons or not. This means that the principle of not allowing the entry of nuclear weapons into the country is not enforced.

In the terms of real politics, Japan has been thoroughly dependent on the United States when it comes to nuclear deterrence. The U.S. assurance that it would provide a nuclear umbrella (Extended nuclear deterrence) is the major reason why Japan does not intend to possess its own nuclear capability.

However, the military nuclear power balance between the United States, China and Russia has already been tilting against the United States. The war in Ukraine further consolidated the ties between Russia and China. It is highly probable that in terms of nuclear strategy, Russia and China secretly agreed to cooperate. A U.S. expert estimates that in the field of strategic nuclear force, if China and Russia join hands and regard the United States as their common enemy, the nuclear power balance will be 2 to 1 in favor of Russia and China.

Regarding Intermediate-Range Nuclear Forces (INF), China, without being restricted by the Intermediate-Range Nuclear Forces Treaty, has unilaterally augmented INF and obtained an advantage in the Indo-Pacific region. As of the short-range nuclear forces, Russia considers them very important in defending its long border line, and it is estimated that Russia has more than 1,800 of them, four to five times as many as the U. S. does.

It is not known how many nuclear forces China owns, but at each level, clearly, China and Russia excel the United States in the number of forces. Despite President Biden’s statement during his visit to Japan and on other occasions, in realistic comparison of forces, it seems evident that the U.S. Nuclear Umbrella has lost its reliability.

If so, Japan has only two options left. To acquire nuclear deterrent power at least as strong as that of Britain and France or to try to augment its conventional armament without the possession of nuclear weapons.

High probability of Japan’s possessing nuclear forces and the U.S. change of policy to acquiesce that Japan and South Korea may possess nuclear arms on their own

American and Japanese experts agree that Japan is potentially capable of possessing nuclear arms on its own. Japan could produce nuclear bombs within several days and owns nuclear fission materials that can be used as fuel for nuclear bombs.

Highly sophisticated technology is not needed and it does not cost much money to design and produce a nuclear bomb. Japan can develop nuclear warheads using super computers without conducting a nuclear test.

Japan owns solid-fueled rockets for civilian use, which can be converted to inter-continental ballistic missiles. Japan will be able to develop nuclear submarines, which can carry submarine-launched ballistic missiles (SLBM) and deploy them within five years. Japan has the ability to develop and manufacture the re-entry part to be used in the ballistic head. This technology, as well as the guidance technology, has been tested successfully by “Hayabusa,” the robotic spacecraft, when exploring the tiny asteroid Itokawa, and others.

The United States has not been successful in deterring North Korea from developing nuclear missiles. In March 2022, North Korea launched successfully an Inter-Continental Ballistic Missile (ICBM) named Mars 17, with a range capable of reaching the entire U.S. territory. In addition, North Korea is developing hypersonic weapons which cannot be counterattacked by the current missile defense system and may carry out its seventh nuclear testing.

Against such threat posed by the North Korean nuclear attack capability, the United States has shifted its policy toward allowing the South Korean possession of nuclear arms.

In 2017, President Trump admitted that the U.S. would lift the restraint on South Korea to build nuclear submarines, Korean ballistic missiles’ ranges and weights of ballistic heads. Following this, South Korea introduced a plan to build a nuclear submarine and in September 2021, launched successfully an SLBM from under the water.

The U.S. policy change to allowing the South Korean possession of SLBMs in the future will be probably applied also to Japan. To possess SLBMs means loading of nuclear warheads, possession of nuclear arms and nuclear proliferation, which the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) prohibits. However, allowing Japan’s possession of nuclear forces will be a rational strategy, considering the inferior U.S. position in terms of present and future nuclear strategic balance against China and Russia.

That is because if the U.S. would not permit Japan’s possession of its own nuclear forces, Japan may succumb to the nuclear intimidation on the part of China and Russia. Regular weapons would hardly enable Japan to cope with the several million-fold destructive power of the nuclear weapons. If Japan should succumb, it would become a subordinate to China and be obliged to serve as a place for China’s military bases. Then, the United States would be destined to lose its hegemony over the Western Pacific.

Without allowing Japan’s possession of nuclear forces, if the U.S. tries to avoid Japan’s capitulation to the nuclear intimidation by China and Russia, the United States would be obliged to send its large-scale ground forces to Japan and fight against the Chinese military to defend Japan.

After all, the only reasonable choice for the U.S. would be to let Japan possess SLBMs carried aboard nuclear submarines with the highest survivability as at least possible nuclear deterrent and means of transportation, in order to protect the U.S. national interest on the verge of life or death, minimizing the risk.

The change in the Japanese people’s awareness and the most reliable way for Japan to obtain its own nuclear forces

With looming crises in the Taiwan Strait and the Korean Peninsula, and facing the worsening situation of collaboration among China, North Korea and Russia, the hitherto-held allergy against nuclear forces by the Japanese people and the anti-nuclear sentiment would no longer sound persuasive. Voices calling for effective deterrent measures and military forces capable of fighting against invasions will become louder, especially among the young generations within Japan.

If Japan’s domestic public opinion changes, possession of its own nuclear forces will be discussed as a realistic political matter. Once it is politically decided, Japan will be able to produce within several weeks reliable nuclear weapons without conducting nuclear testing and acquire the most reliable deterrent—possession of nuclear forces of its own.