Our treaty with the US involves a number of tracking stations such as Pine Gap. This gives both Australia and the US a chance to see a missile launch as it leaves the ground and to be able to track it by a wide variety of radar facilities including ship-based radar.

A missile this size is big and obvious to radar. We can't get an accurate idea of height until one is directly overhead on its way to the target, but we can get a rough idea, as well as a known speed, so that we can work out the intended target fairly accurately.

This does not give us long to prepare – 30 minutes to an hour or two would be a global time of the flight from a close target to anywhere on Earth.

If you are a country about to test a missile, letting the world know about a test and ensuring that your test target is nowhere near a real target ensures that the world does not react aggressively. Inter-Continental Ballistic Missiles can only do small changes in direction in flight. Once launched, if they are off track, they need to be aborted immediately.

There is little that can be done by the target country once a nuclear missile is launched. Most missiles are multi-warhead-capable and deploy their nuclear loads high in the upper atmosphere away from most defence missiles. The US and the USSR/Russia adopted a strategy of mutually assured destruction. The target country would see the incoming missiles and would retaliate with their nuclear arsenal. Everyone was too scared to launch a first strike on that basis, but an accident or a rogue military group may have caused an atomic war that may have destroyed the world.

Australia is not a nuclear nation and would look to the US to assist in its protection. We also do not have the missiles to destroy incoming nuclear weapons.

Our distance from the enemy is important. Even if the north of Australia came into range, Darwin is not a likely target and Australia would really only be threatened if Brisbane came into range of a nuclear power. International retaliation would be ensured by such an attack.

Response by: Robert Brand, CEO ThunderStruck Aerospace

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