It's inevitable that nations will modernize their nuclear arsenals, as participants in this roundtable agree. Two authors—Lu Yin and I—further agree that modernizations should be managed so as not to impede nuclear arms reductions and, eventually, complete disarmament. Matthew Kroenig, meanwhile, writes that "[c]omplete nuclear disarmament may be desirable" but he seems to discount it as an option worth pursuing. "[A]chieving it," he writes, "will require nothing less than a major transformation of the international political system."
One can agree with that—but if reaching nuclear zero is desirable, as Kroenig admits, one ought to ask how nuclear-armed nations can advance this goal in the near term. Unfortunately, it's difficult to discern in Kroenig's approach to modernization any strategy through which the world could become a safer place. Instead, Kroenig focuses much of his argument on why the United States should maintain its military "dominance."
Kroenig writes that the United States has enjoyed "conventional military dominance" over the past two decades—and he is correct about this. During much of the two decades in question, US military expenditures were on the rise. The US military budget remains the world's largest, accounting for more than one-third of global military spending. China and Russia combined spend less than half as much on their militaries as the United States spends on its own. Yet Kroenig argues that "the US conventional advantage is eroding as Russia and especially China build up their non-nuclear military capabilities."
But exactly how much dominance must the United States enjoy—and at what price? For that matter, is US military dominance consistent with Washington's professed leadership in building a better, more harmonious world? A world free of war and fear? The sort of world in which, to borrow Lu's language, "[t]he practical reasons for possessing nuclear weapons would gradually disappear"?
How much is enough? Kroenig writes that "as the United States has slashed the size of its arsenal, other countries have moved in the opposite direction, building up their nuclear forces." But in fact, Russia, France, and the United Kingdom are decreasing their arsenals. Admittedly, India and Pakistan are increasing their nuclear forces—and China is likely doing so as well. But to the extent that growth in China's arsenal poses a problem, the solution lies in dialogue about transparency and arms control, not in military dominance. Such dialogue could lead toward capping the nuclear arsenal of China's neighbor India, which perceives China as a threat. This could make it possible to cap the nuclear capabilities of Pakistan, which perceives India as a threat. A build-up in the US arsenal, on the other hand, would not change perceptions or trends in South Asia.
The real question is how much modernization is enough. Which sorts of modernization would create obstacles to further cuts? Which would be neutral? Which might even contribute to disarmament? An example of a program that clearly undermines further disarmament is the ongoing US effort to improve the fusing systems of long-range land- and sea-based ballistic-missile warheads. The better accuracy and higher kill power of these warheads would dramatically reduce the survivability of Russian silo-based missiles. This in turn would make nuclear war more likely.
Kroenig seems to consider only two near-term options for managing the US nuclear arsenal, and both are extreme. One option is "allowing the US arsenal to rust away." The other is maintaining "a robust nuclear posture and fully moderniz[ing] … nuclear forces, as planned." But these two choices are not the only ones—many more options lie in between. For example, the United States could scale back plans to replace its existing fleet of submarines—that is, buy fewer boats—or it could delay plans to build new nuclear bombers. It could also abandon the program, mentioned above, aimed at building up first-strike counterforce capabilities. This would give the next round of nuclear reductions a better chance of success.