Recently Donald Trump implied that he might be okay with South Korea and Japan acquiring nuclear weapons. Shortly after these comments were made, Japanese Prime Minister Shino Abe made a shocking claim of his own. Abe stated that the Pacifist constitution that Japan adopted after the Second World War does not prohibit it from processing nuclear arms. The subtext is clear; Japan can have a nuclear bomb if it wants to have one.
Why states pursue nukes
States pursue nuclear weapons for one reason: security. A nuclear bomb is the ultimate deterrent to any adversary. Israel built bombs to deter the Arab world from attempting to destroy it. India and Pakistan built bombs to deter each other and North Korea uses it’s arsenal as a source of terror and a hedge against regime change by the U.S and South Korea.
The Domino effect.
The problem with nuclear proliferation is that it creates a positive feedback loop. Once a nation acquires a nuclear device it’s enemies feel the need to either build their own, or upgrade their arsenals to keep up. This competition almost always creates an arms race as nations struggle to deter each other with ever greater nuclear capacity.
History’s most famous example of this was the United States and the Soviet Union during the 1950s and 1960s. The Soyuz space vehicle that launched Sputnik in 1957 was essentially an R-7 intercontinental ballistic missile with a satellite payload instead of a warhead. The Sputnik launch sent waves of panic through the United States and planted the idea that the U.S was falling behind in missile development.
What resulted from Sputnik’s launch was a crash program to arm the U.S with ICBMs to fill the supposed “missile gap”. By the end of the 1960s the U.S was fielding 6000 strategic nuclear warheads. This was about double the roughly 3,000 that were deployed at the beginning of the 1960s. Most of these increases were due to increasing numbers of MIRV capable nuclear missiles that had been developed because of the perceived Soviet threat.
The U.S and Soviet Union continued to upgrade their weapons throughout the rest of the Cold War. By the end of the Reagan administration the U.S was fielding 14,000 nuclear warheads, six times the number deployed in 1960. Systems like the Ohio Class submarines were developed and deployed. With 18 built, each submarine could launch 288 warheads on 24 missiles.
If Japan decided to obtain a nuclear weapon the results could be disastrous and potentially apocalyptic. What happened between the U.S and the Soviets could happen between Japan and China. Japan is allied with the United States and has competing claims with China in the East and South China Seas. China therefore, views both nations with suspicion. The Sino-Japanese relationship is especially strained as there is mutual animosity on both sides and competing claims over the Senkaku Islands.
If Japan were to go nuclear it could threaten the Non-Proliferation Treaty and encourage other states in the region to follow suit. South Korea might attempt to obtain a nuclear bomb to compete with the North. Other nations would also be tempted by the thought of an ultimate weapon to fight off the growing Chinese threat.
Should the taboo on nuclear proliferation be broken in Asia Taiwan may see an opportunity to preserve it’s independence through nuclear deterrence. Taiwan has the necessary expertise to build a bomb as it had an active nuclear weapons program in the past. Pressure from the U.S and international community had destroyed those ambitions but the political change brought on by another nuclear power in Asia could revive them.
China’s current forces are suspected to consist of 50 to 60 ICBMs and 150 tactical nuclear weapons. The weapons range from tactical to strategic with yields ranging from 15 kilotons to five megatons. While these bombs are good enough to deter current regional adversaries like India, the force structure would likely be insufficient to deal with multiple nuclear powers at once.
If a nuclear arms race kicks off in Asia China will need to reevaluate it’s own nuclear forces. China would undoubtedly see a nuclear Japan as a major threat and respond with it’s own nuclear build up. This in turn would pressure other adversary nations to build up their own arsenals.
A nuclear war between Japan and China also has a good chance of bringing the U.S in as American soldiers would likely be killed in an attack against Japan. China would have to account for this and more launchers would be necessary to ensure Chinese weapons wouldn’t be wiped out in a counter strike by American missiles and bombers.
Japan must never have the bomb.
Let me be clear; Japan must never be allowed to have a nuclear bomb. The potential for a Asian destabilization is too great. A Japanese bomb would encourage other nations to arm themselves and force China to expand it’s own nuclear arsenal. The result would be a nuclear arms race not seen since the 1960s and the potential for a nuclear war in Asia that could kill tens of millions.
Any miscalculation between the two powers could result in a nuclear war between Japan and China. Because Japan is under the American nuclear umbrella this war could quickly turn into a global nuclear conflict involving the United States. Should China conduct a strike on Japan the United States would be forced to act. This means counter force, which means a full blown global nuclear war.