Missile defence for Australia? Expensive and probably not wise
Following the most recent tests by North Korea of a missile that might be able to hit Alaska, the prospect of a direct threat to Australia from the Kim regime is exciting the Australian defence debate. Over the weekend, former Prime Minister Kevin Rudd and Prime Minister Malcom Turnbull weighed in in the issue. And yet, in a debate based on analysis-by-soundbite, a range of basic factors - the significance of the threat; the systems that might be useful to defend Australia; indeed, what ‘missile defence’ actually is - risk being very much confused.
First, sooner or later, Australia will come into range of North Korean, possibly Iranian and other countries’ missiles, as the advance of manufacturing technology make ‘rocket science’ increasingly easier than the proverb suggests. However, threat is always a combination of capability, vulnerability and intentions. A missile able to hit the continental US would also give North Korea the capability to hit Australia. But given the importance of US security guarantees on the Korean Peninsula, Washington and its allies have genuine reason to worry about North Korea’s coercive intent directed at the US. Australia, however, is a bystander or bit player at best among the powers of Northeast Asia.
Moreover, while it is true that Australia’s population is among the most concentrated, this does not necessarily translate into a particular vulnerability against a rudimentary North Korean nuclear weapon. The 15 kiloton bomb dropped on Hiroshima, about 2-3 times more powerful than anything North Korea has tested so far, created 5PSI overpressure over a diameter of 3.5km, where 100% fatalities inside buildings would have to be assumed*. Given the low population density of Australia’s large cities, an attack with such a weapon would likely cause fatalities closer to the upper four-digit figures than in the 100,000s, let alone anything in the Cold War nuclear holocaust scale that still reverberates in public imagination and that seems to place any nuclear weapons threat beyond cost-benefit calculation.
Second, the development of North Korean ballistic missiles is just one example of the erosion of the security afforded to Australia by its geographic remoteness. Russia’s demonstrative use of long-range precision attack cruise missiles in Syria, fired from corvettes in the Black Sea as well as submarines in the Mediterranean, is indicative of capabilities increasingly available and deployed in Australia’s own region. China now maintains a regular submarine presence in the Indian Ocean and its large air bases on artificial islands in the South China Sea have brought the unrefuelled range of its bombers significantly closer to Australia’s shores.
Admittedly, cruise missile defence is, technologically, a different problem to defence against ballistic missiles, but it is exactly for this reason that it is important to keep in mind that defence policy and investment must always balance different threats, and must prioritise on the balance of probability and potential harm. In the 1970s and 1980s, Australia struggled to make the ‘Defence of Australia’ doctrine seem relevant, given the rudimentary capabilities of its neighbours. In the 1990s and 2000s, it was increasingly distracted by commitments outside the Asia Pacific. In the future, the difficulty of defending our large continent will increasingly preoccupy our defence policy. But the threat from North Korean missiles will only be one element of that new challenge.
Third, defending Australia against intercontinental ballistic missiles would require some of the most expensive and least versatile pieces of military kit available. Many missile defence interceptors — including Arrow, Patriot, SM-2 and THAAD — are useful against a range of ballistic missiles as well as ‘air-breathing’ (cruise missiles and aircraft) targets. Not so interceptors that can destroy ICBMs, which have to work in the empty vacuum of space. At a cost per missile of about US$90 million —excluding silos, command & control systems or radar sensors, the Ground-Based Interceptors (GBI) the US placed in Alaska and California are prohibitively expensive and still of uncertain reliability in their current configuration. Yet GBI remains the only system specifically designed to intercept ICBMs.
To read the entire article by Stephan Fruehling, visit the Lowy Institute website.
