[Cryptography] Spooky quantum radar at a distance

[Jerry Leichter]

> Picked up is one thing. Shoot down? If you don't have any
> interceptors, you will be relying on SAM missiles.
And even then, the days of visual dogfights and machine guns are way behind us.  You're probably shooting at the other guy from over the horizon using radar-guided munitions.

> Stealth is not about perfect undetectability, but about reducing the
> effectiveness of long-range radar based weapons, which for physics
> reasons have to use high frequencies. The engagement range of a
> stealth aircraft is longer than that of its opponent, providing ample
> opportunities to destroy the opponent first.
There are and always will be plenty of ways to *detect* the presence of aircraft.  During the Vietnam war, the North Vietnamese dug pits designed to resonate around the sound frequencies produced by incoming aircraft.  "Spotters" were stationed in the pits and sounded the alarm.  With enough pits they could get a pretty good idea of the general track being flown.  Good enough to alert potential targets; nowhere near good enough to get a shot at a plane.

As you say, perfection isn't the goal - it's getting in, doing the job (to be really euphemistic about it), and getting out without getting shot down.  Anything that delays or blurs your opponent's reaction is good enough.

Perfect undetectability is needed only if your goals are political (hiding what was done and by whom).  And even then, plausible deniability is likely good enough.

                                                        -- Jerry