Yeah it is possible. It can either be shut down, or its accuracy can be degraded. See for example http://www.equipmentworldmagazine.com/apps/news/articleeqw.as

Yeah it is possible. It can either be shut down, or its accuracy can be degraded. See for example http://www.equipmentworldmagazine.com/apps/news/articleeqw.asp?id=45940 http://www.equipmentworldmagazine.com/apps/news/articleeqw.a... How is easy - all the GPS satellites belong and are operated by the US air force (see video segment above). I think the EU is/was trying to get a competing network up there in order not to be so totally dependent on the whim of the US President. I don't know what the status of that is.