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Son of a gun

PRESIDENT George Bush outlined his vision of a national missile-defence
programme last week. Many critics say the scheme will be ineffective and
staggeringly expensive.

Bush revealed sketchy details of his concept of a 鈥渓ayered鈥 defence system,
which would force enemy missiles to evade a series of ground, sea and air
defences. The scheme is far more modest than Ronald Reagan鈥檚 space-based
Strategic Defense Initiative (SDI) or 鈥淪tar Wars鈥 proposal of the early 1980s.
SDI sought to block a full-scale attack by the now defunct Soviet Union, while
Bush鈥檚 proposed system seeks only to stop a few missiles from a rogue state.

One layer of the proposed system would be the ground-based National Missile
Defense System originally developed under the Clinton administration. After a
failed test last year, Clinton passed the job of deciding whether to deploy the
system to his successor, pending further tests that are still to be carried
out.

Other layers would be provided by interceptors based at sea or in the air.
These 鈥渃ould provide limited but effective defences鈥, Bush said. Ships fitted
with sea-based defences could be posted off North Korea. Air defence would be
centred on the Airborne Laser, a powerful chemical laser mounted in a customised
Boeing 747. Planes carrying lasers could fly close to suspect countries such as
Iraq and zap missiles as they rise into the sky.

Bush dismissed the 1972 Anti-Ballistic Missile (ABM) treaty, which restricts
the deployment of systems to counter ballistic missiles, as out of date. 鈥淲e
must move beyond the constraints of the 30-year-old ABM Treaty,鈥 Bush said.
鈥淭his treaty does not recognise the present or point us to the future. It
enshrines the past.鈥

The US will not accept the ABM treaty鈥檚 terms for much longer, Bush said. 鈥淣o
treaty that prevents us from addressing today鈥檚 threats, that prohibits us from
pursuing promising technology to defend ourselves, our friends and our allies is
in our interests,鈥 he said.

Henry Cooper, a diplomat under the Reagan administration and head of SDI
during the presidency of George Bush senior, agrees. 鈥淲e need to abandon the ABM
treaty if we鈥檙e going to be truly effective at developing advanced defences,鈥 he
told a meeting of the American Physical Society in Washington DC last week. He
says the limitations imposed by the treaty have led to a missile defence plan
that is 鈥渢he most complex, least effective and most expensive option鈥.

Others argue that Bush鈥檚 proposed layered system can鈥檛 work. Robert Sherman,
a nuclear analyst with the Federation of American Scientists in Washington DC,
told New Scientist that ground, sea and air defences would each pick up only 5
per cent of passing targets.

One problem is that ground-based defence is difficult. Missiles targeted in
mid-flight, when their boosters have burnt out, are hard to spot from the
ground. Airborne defence is problematic too. Scientists have yet to show that
powerful lasers can overcome atmospheric effects that diverted laser beams from
their targets in earlier tests.

On top of that, Bush has not put a price on his defence system. Sherman
predicts that this will be 鈥渢he most expensive project in human history, deep
into the hundreds of billions of dollars鈥.

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