France has a new, $400 million, satellite tracking system, and is using it to blackmail the United States. Using special radar and telescopes, the Graves Radar System (GRS) seeks to keep track of satellites and space debris. Currently, the largest satellite tracking system, the U.S. Defense Department's Space Surveillance Network (SSN), has been doing this for decades. But it has long been known that, while the SSN public catalog lists huge numbers of satellites and space debris, it leaves out many low flying American spy satellites. The new French system has discovered about two dozen of these, and has offered to keep details secret if the U.S. will reciprocate and not publish similar data on some French spy satellites. If you know the orbits, or other details, of these low flying birds, you can hide some activities, but keeping stuff under cover when the satellites come over. Since all this involves highly classified projects, any agreements in this area will probably also be classified.