Why Turkey Needs a Light Touch - Politics - The Atlantic(...)any sort of missile defense shield over Europe all but requires the U.S. to place its highly advanced AN/TPY-2/TPSX X-band radar system in Turkey.
Actually, it's either going to have to be in Turkey, or it's going to have to be in space. And Russia has made it clear that a space-based radar system would violate its interpretation of the START II missile defense treaty, while a radar system in Turkey, farther away from Russia's perimeter, would be acceptable. The fear is that the radar, highly sensitive and studded with senors that allow it to continuously track multiple targets and intercept them at above-atmosphere levels wouldn't be passive enough for Russia's territorial integrity.
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