Why hypersonic developers have narrow window to enact arms controls

Hypersonic missiles magnify old challenges to strategic stability and generate new ones. There are two types of new challenges. One is the ability of such missiles to penetrate all current missile defences by travelling at speeds in excess of Mach 5 while manoeuvring through their trajectories and flying relatively closely to the contours of the earth.

The other challenge is that such missiles may afford only seconds of warning to current sensor systems, forcing countries under attack to make hair-trigger decisions as to how to react. Current types of missiles may pose these challenges to a lesser extent. But hypersonic weapons are intended to be so much more capable that they constitute game-changers.

China, the USA and Russia (the Big Three) are racing to develop such systems. France (and others in Europe), Japan, India, and Australia are pressing ahead with the technology, too. How can they avoid destabilising consequences? And how can governments prevent hypersonic missiles from spreading to less mature defence establishments?

CONTROLS

There are two broad approaches: bilateral or multilateral arms control and unilateral controls to inhibit proliferation. Arms control can limit forces by the agreement of all parties. Non-proliferation can limit forces by agreement only of potential exporters or of governments imposing sanctions.

Strategic arms control talks – by the USA, Russia – and perhaps some day China – now include hypersonic missiles on proposed agendas. But it is far from clear whether such missiles will be subject to new limitations. Russia has offered to count hypersonic missiles under the restrictions of the New START Treaty, but with a catch. The Russian foreign ministry insists that a precondition for hypersonic discussions is a US willingness to place limitations on missile defences – a condition repeatedly rejected by the USA. The USA insists that China must join such talks, but China has refused to negotiate limits on its nuclear forces.

Other conceivable arms control approaches might include more nations than the Big Three. Such approaches might range from numerical limitations to test bans to outright bans on hypersonic missiles.

In addition there are approaches to hindering the proliferation of hypersonic missiles to other nations. Such efforts could start with the Big Three. China is unlikely to want to see Japan, India, and the arc of nations in between acquiring such weapons. Similarly, Russia is unlikely to want to see such systems acquired by Japan or nations in eastern Europe. But how can this proliferation be hindered?

Hypersonic technology itself offers an answer. The technology is exceedingly difficult to apply in practice. Missiles able to operate at hypersonic speeds must cope with air flows of thousands of miles per hour that heat and distort airframes, sensors, and communications, among other major difficulties. A few countries beyond the Big Three may be able to acquire all the necessary technologies and apply them successfully, but most nations will need to import all-up systems or their major components. 

If hypersonic missiles follow the commercial paths of other systems, the Big Three will ultimately start selling them to governments they consider to be friendly. But conceivably, the Big Three could agree early on to embargo the export of complete systems or their major components. A RAND Corporation report entitled: “Hypersonic Missile Non-proliferation” recommended that they do just that.

Such a venture would require at a minimum the co-operation of the Big Three, but other governments could certainly join. There are still a few years available before industrial interests begin pressing for exports of hypersonic missiles, so there is a window of opportunity to address hypersonic issues, not only in talks on strategic arms but also on non-proliferation.