For some, it's 'Son of Star Wars', for others the project to hit a speeding bullet with another bullet, but whatever you choose to call it, Australia signed up today to America's missile defence plans. Our defence scientists are to join the United States in trying to create a system to shoot down ballistic missiles. Various US estimates put the cost at anything from $30 billion upwards. But the Federal Government says Australia's initial role and costs will be modest. The joint Australia-US intelligence facility at Pine Gap in the Northern Territory and Australia's over-the-horizon radar expertise will contribute to the research. The Defence Minister, Robert Hill, spoke to Graeme Dobell.

Senator, what role do you see Australia playing in the research and development of an anti-missile defence system?

Australian defence scientists have unique technologies that we think can contribute. It's obviously a very small part of a huge project, but each small part is important.

What role would the joint facility at Pine Gap… will our over-the-horizon technology play?

Well, we have for a long time provided early warning advice on the launch of ballistic missiles. That obviously continues to be a critical aspect of defence in being able to defeat those missiles, whereas in the past it was a deterrent in terms of the knowledge that enables the missile to be defeated during the flight. It's very important and will continue to be.

Do you think the science is do-able? Can 'Son of Star Wars' actually be made to work?

It's not 'Star Wars' in the... the original Star Wars was a concept of missiles being launched from space and the like. This is not that at all. It's missiles being launched from land or from sea to defeat a ballistic missile that's been fired, to defeat at either the launch phase or the cruise phase or on re-entry into the atmosphere, and the technology is already there to do it. The exercises that are taking place have been successful on land and on sea. There's a long way to go in the development of the system, but the first part of it will actually be deployed by the US next year.

And Australia you think can contribute to creating the technology for a, in a sense a speeding bullet to hit a speeding bullet?

Some of our radar technologies really are state of the art, small sized, active, Phased Array Radar, our technologies are arguably ahead of the best in the world.

Do you see Australia in the future needing to deploy anti-missile systems, on Australian soil, not just on Australian ships?

We don't have any plan for that, that's well out into the future, but we believe to have the knowledge and the capability to be able to do so if it's decided in the future is important.

Is this directed basically at North Korea? Is this a response to a North Korean threat?

No, the missile defence systems have really been developed out of a proliferation of long range missiles and a proliferation of mass destruction war heads and also the unpredictability of the global strategic environment. In the Cold War days, there was certainly a threat, but it was a very predictable threat and it was answered by deterrence. These days where there is a proliferation of these missiles, they need to be defeated in another way. New technologies have provided that other way.

So it isn't just a response to possible rogue states like North Korea? It's looking at the missile capabilities of states such as China and India, which are developing missiles which could eventually reach Australia?

No, the US has said that it's the rogue state element that really has driven the process and I think that's correct.

It is about capabilities too though, isn't it?

Because well behaved orderly states, there are other ways in which you deal with these matters – through diplomacy and many other ways. It's the rogue state that won't play by the rules that provides the real threat, and this is one way in which that threat can be reduced.

The Defence Minister Robert Hill, speaking to Graeme Dobell.