> Behalf Of Russell Chapman
>As long as the shield is based on anti-missile missiles, the
> reaction time from detection to confirmation to launch to
> acceleration means the
> incoming missile has to be too close during interception.
>
And you also need to either hit every decoy deployed or be able to
discriminate between live warheads and decoys. Decoys are very easy to
make - even balloons released before reentry make all the right displays on
a radar screen. Very small reentry vehicles with dinky little transponders
can even be programmed to vary their flight path to really confuse the
defending system. So you might have to launch 2 missiles at each one coming
in to make certain you hit it.
Any boosters disintegrating along the flight path can act as decoys. As they
could also act as a live vehicle by reentering with a bomb still left on
board. Which means you have to hit, and kill, EVERYTHING. Nuclear and
thermonuclear weapons have a pretty big footprint so accuracy isn't really
important.
And on the ground you have to put up with an absolutely hellish Electro
magnetic pulse that will wipe out almost all civilian electrical systems,
right down to your internet-enabled toaster and car-management system.
If you don't hit everything, your defence hasn't worked.
That's the big point: this is an all or nothing defence system your
government is trying to foist. The technology isn't there and will take many
years to develop. If it can be done. But in that same range of years,
anyone who gets nervous about US power has one option - build lots and lots
of missiles. And that job is much easier than developing an all or nothing
defence.
Brett
