DIPLOMACY ДИПЛОМАЦИЯ

A SHIFTING ASIAN NUCLEAR ORDER
moving towards placing multiple warheads atop certain classes of missiles, it’s probably
going to deploy more warheads in the future than it has in the past. But modernisation isn’t
just about nuclear weapons. For example, China’s development of the DF-21 – a ballistic
missile with a manoeuvring warhead intended to target US aircraft carriers at sea – plays into
the bilateral relationship at the level of grand strategy. If China can deny a large portion of the
Western Pacific to major US surface ships, the importance of other forms of US assurance
to Washington’s allies must surely increase. And if China can transfer its expertise in
manoeuvrable warheads from its conventional missiles to its strategic nuclear force, that
could help to counter US efforts in ballistic missile defence (BMD).
BMD is a sensitive issue for China. The intensity of Beijing’s reaction to the scheduled
deployment of a US THAAD (terminal high-altitude area defence) battery in South Korea in the
wake of North Korea’s recent nuclear and missile tests is testimony to its anxieties. It’s hard
to know what might offset its concerns. In recent years, the US has tried to reassure China
that long-range Chinese strategic missiles aren’t the target. The Americans have attempted
to argue that North Korea’s capabilities are their target, and – given the limitations of the
existing BMD systems – that’s probably true. But Chinese short-range and medium-range
conventional missiles already threaten US allies and forces in theatre, and the sophistication
of that threat is going up, not down. Beijing must be aware that the growth of Chinese missile
capabilities is also a concern in Washington, so its judgement that North Korea is merely one
driver of US BMD deployments in the Asian theatre is likely to be correct.
In short, it’s plausible that US BMD assets in theatre would have a growing capability
against some fraction of the Chinese arsenal. Of course, that doesn’t mean they would
achieve an effective defensive capability against China’s strategic assets anytime soon.
Ballistic missile defences work best against shorter-range missiles, fired in small numbers
and deploying only simple or no countermeasures. Once any of those three factors changes,
interception becomes harder. If all three change, effective defence becomes impossible.
China’s concerns, though, don’t centre only upon the capabilities of regionally based
interceptors. Regionally deployed Patriot units defend only a small footprint, and even the
THAAD batteries don’t reach much further than a couple of hundred kilometres. Of more
concern are the surveillance assets deployed as part of the units, in particular the AN/TPY-2
transportable X-band radar. Beijing fears that such radars, used in their forward-deployed
role rather than their terminal defence one, might provide advanced early tracking data to
other parts of the US global BMD system – thereby increasing the likelihood of successful
defence against China’s small ICBM fleet over coming years.
For the near future, such concerns sound overblown. The AN/TPY-2 certainly has the
capability to provide early tracking data on some Chinese launches, and it can readily
transfer that data to other parts of the system. After all, one of its roles in South Korea
would be to monitor North Korean long-range missile and satellite launches. But that data,
by itself, probably isn’t going to be the key determinant in the successful interception of an
ICBM. And China has a number of options of its own to improve the prospects for successful
penetration, including the deployment of a more advanced suite of penetration aids atop
its strategic missiles and, obviously, the installation of MIRVed payloads. Some of those
developments are already in train, suggesting that China’s moving to ensure the continuing
effectiveness of its strategic nuclear arsenal in coming decades.
Besides, it’s unlikely the US would hold back completely from improving its defences
against short- and medium-range missiles merely to accommodate China. Beijing appears
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ДИПЛОМАЦИЯ 18/2016