Both South Korea and Japan have recently hinted at their renewed interest in acquiring nuclear weapons. In February, after North Korea conducted a nuclear test, an article in South Korea’s daily newspaper, The Chosun Ibo, reported that “there have been voices calling for South Korea to develop a nuclear weapon of its own.” Then in April, Japanese Prime Minster Shinzo Abe stated that the Japanese constitution does not preclude the country from possessing and using nuclear weapons, in spite of Japan’s deeply ingrained cultural aversion to them.
The possibility that two signatories of the Nuclear Nonproliferation Treaty could express an interest in building weapons of mass destruction has raised some alarm among nonproliferation advocates. Henry Sokolski of the Nonproliferation Policy Education Center recently penned an op‐ed in The Wall Street Journal titled, “Japan and South Korea May Soon Go Nuclear” and warned that “plutonium stockpiles are rising.”
In reality, such a scenario is unlikely, particularly that it will happen “soon.” Although there is popular support in South Korea for acquiring nuclear weapons, there appears to be little backing among the elite. With the country facing a presidential election next year, any immediate revamp of its nuclear program would be read as precipitous and cynical posturing. Such a drastic policy shift would be even more unlikely in Japan, where public opposition to any sort of militarization has slowed even minor steps toward greater independence in defense.
Despite clear signs that neither country has serious intentions of building nuclear weapons, nonproliferation advocates, such as Mark Fitzpatrick of the International Institute for Strategic Studies, complain that even the mere mention of allies building atomic bombs weakens the credibility of the nuclear umbrella, which is Washington’s pact to go to nuclear war to protect its allies, however small. If nations such as Japan and South Korea consider adopting nuclear weapons, then what reason does Washington have to guarantee their defense? And if Washington begins questioning its own commitments, it could push allies to acquire nuclear weapons. In the end, advocates argue, such musings could undermine deterrence. This line of thinking, however, is clearly outdated.
Since the Cold War, the United States’ nuclear obligations have not only shifted away from maintaining the perception of “massive retaliatory” capabilities against Soviet Russia, but have also metastasized. The United States has backed South Korea since the 1950s against North Korea and its nuclear‐armed allies, China and the Soviet Union. Of course today, China and Russia are unlikely to attack South Korea, but the threat from North Korea, which is developing its own nuclear arsenal, remains high. As for Japan, after its devastating defeat during World War II, which was highlighted by the nuclear bombings of Hiroshima and Nagasaki, it signed a treaty handing its security over to the United States. Even now it retains a formal constitutional bar on the creation of any armed forces, spends barely one percent of its GDP on its “Self‐ Defense Force,” and imposes arbitrary limits on the latter’s role.
Beyond these treaty‐based commitments are non‐written ones, whether conventional or nuclear, intended to deter other nations from using weapons of mass destruction. For example, Taiwan expects U.S. support in the face of any cross‐strait aggression. Australia is nuclear capable and is less vulnerable to Chinese aggression, but it is a long‐time U.S. ally and also relies on Washington. In the Middle East, Turkey, Egypt, and Saudi Arabia demand, to some degree, that the United States continue offering military assistance and tempering Iran’s nuclear ambitions.
Unfortunately, the cost of honoring these many commitments outweighs the benefits. The United States may have to maintain an ever‐increasing and diversifying store of nukes and weapons. Even conventional commitments significantly add to the United States’ defense burden. South Korea possesses an economy 40 times the size of North Korea’s and a population that is two times as big; yet it expects a perpetual U.S. troop presence. So does Japan. The Middle Eastern nations presume permanent U.S. military involvement in their region.
In this regard, U.S. armed forces are configured more for the projection of power to protect allies, which is extraordinarily expensive, than to deter attacks upon its homeland and protect its direct interests. Reducing unnecessary commitments would allow a significant downsizing of the military, such as radically cutting back the army, closing a number of foreign bases, and trimming other defense services. It is possible that a less interventionist approach could ultimately save at least one‐fourth of planned U.S. military spending, which would be about $150 billion of this year’s $600 billion plus in military outlays.
But the biggest cost is the human one, since maintaining the nuclear umbrella increases the risk of conflict. Hypothetically, if Washington were to aid any of these states in the face of a nuclear attack, it would expose itself to a retaliatory attack on U.S. soil, which would put the lives of thousands if not millions of its own citizens in jeopardy for modest or even minimal gains. Without a Cold War, the Republic of Korea is not particularly important to U.S. security; moreover, Seoul, which is the world’s 13th largest economy, is capable of defending itself. It could also field a much larger conventional force and South Korean experts have boasted that the country has the capability to produce a nuclear weapon in less than two years.
Moreover, many of the risks that Washington’s help is meant to fend off are fanciful. No one could really imagine a Chinese armada sailing into Tokyo Bay. And even if war did arise between Japan and China over the Senkaku/Diaoyu Islands, it is unlikely that Washington would actually use nukes against China for such low stakes. The question of whether nuclear defense alliances are necessary begs another: Do they even work? Historically, deterrence often fails. Both World Wars featured defensive alliances that failed to prevent conflict. Instead, the military pacts expanded the conflicts.
One possible solution is to replace the nuclear umbrella with “friendly” proliferation. The United States could allow its Asian allies—Japan, South Korea, and Taiwan—to develop their own deterrence against China and North Korea. If conflict emerged, the United States would not automatically be dragged into war. Washington could reconfigure its military for its own defense, rather than overstretch itself by providing offense for every one of its allies across the globe.
To be sure, even friendly proliferation would have negative consequences. But they are not as alarming as commonly thought. Permitting South Korea and Japan to build nuclear weapons would undermine the Nuclear Nonproliferation Treaty, but in reality, so has Israel’s possession of nuclear weapons, Washington’s acceptance of India as a nuclear power, and allied negotiation with Iran to forestall its development of nuclear weapons. Nonproliferation policy always has been tempered by changing circumstances. Washington should allow the same in northeast Asia.
Proliferation could also accelerate the regional arms race, particularly given that there is currently no known limit to North Korea’s nuclear ambitions. China might also speed up improvements to its nuclear program in response, but it would be difficult, if not impossible, for such efforts to overcome the capabilities of U.S. allies. Missiles from just one Japanese submarine could take out China’s most important cities, irrespective of Beijing’s retaliatory capacity.
Another downside to proliferation is that the greater the number of nations with nukes, the higher the risk of accidents, mistakes, leakages, misuse, and more. But these risks are fairly low compared to aggressive behavior that the nuclear umbrella encourages—essentially, it rewards U.S. allies into being more aggressive risk‐takers. In the 2000s, the emboldened Taiwanese President Chen Shui‐bian routinely challenged Beijing. Georgia started the 2008 war against Russia with the apparent assumption that Washington would come to Tbilisi’s aid, if needed.
Friendly proliferation could also increase nuclear tensions and instability, especially during the transition phase when countries are in the process of increasing their stockpiles. Other powers might be tempted to thwart their attempts at building nuclear weapons by launching an attack. But countries secure in their deterrent capabilities, such as China, are less likely to see a fledgling nuclear power as a threat. For example, a half century ago, the United States and the Soviet Union, comfortable with their own capabilities, decided not to stymie China’s nascent nuclear weapons program. If North Korea feels threatened by nuclear programs in South Korea and Japan, Washington could maintain its security guarantee until its allies develop their retaliatory capabilities in full. That should be enough to keep Pyongyang in check.
Although discussing a change in U.S. proliferation policy might be unsettling, there needs to be an open debate on the issue, which has not taken place so far. There are, of course, sound reasons why Washington should be wary of encouraging proliferation, but U.S. strategies should be cognizant of changing circumstances. An approach that made sense in 1950 or 1960 isn’t necessarily relevant in 2016. That includes forbidding allied states from responding in kind to aggressive, provocative opponents such as North Korea. Pyongyang is a nuclear power and it is determined to expand its arsenal and build intercontinental missiles. Washington cannot and has not stopped it and China will not prevent it from doing so. So what now? It is foolish not to at least consider allowing, if not encouraging, Seoul and Tokyo to develop countervailing weapons.