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How To Cloak Objects At a Distance
KentuckyFC writes "All invisibility cloaks to date work by hiding an object embedded inside them. Now a group of physicists have worked out how to remotely cloak objects that sit outside a cloaking material. The trick is to make the cloaking material with optical properties that are exactly complementary to the space outside them. Complementary means that the material reverses the effect the space has on a plane wave of light passing through it. To an observer this space would appear to vanish. The scientists say that to cloak an object sitting outside the cloaking material, first measure its optical properties and then embed a "complementary image" of the object within the cloak. So a plane wave is first distorted by the object but then restored to a plane by the complementary image of the object within the cloak (abstract). An observer sees nothing. This method has another benefit. Objects hidden in conventional cloaks are blinded because no light enters the cloaked region. But objects that are remotely cloaked like this should still be able to see their surroundings."
I'll go you one better - over in the Middle East, there were apparently some insurgents/terrorists/whoever using the tried-and-true method of hiding in a sandstorm before attacking or while attacking. It worked well in the good old days, but we now have these things called satellites and night-vision and infrared and technology, where they're pretty much sitting ducks now.
... in your argument is "against another sophisticated military".
However this is rarely the case. Nowadays most engagements the US Military is involved in are against people with little more than 25-50 year old weapons. The problem the US Military has is the on the ground war against these kinds of insurgents - this tech. would be invaluable against them, you could approach a camp on foot without fear of being seen.
Well, no, actually they take a photo of the subject, make a sort of translucent negative, and put it in front of the object and make the object disappear from view. Slightly more ingenious because the background can change.
Not sure how they handle the "light behind the 'cloaked object' isn't shining through it" scenario. Presumably you could bend the light around the object and back into it's orignal path - but that's the 'embedded cloaking device' as far as I can tell.