That's one of those things that makes me laugh when people accuse the US gov't or military of various conspiracies. They can keep things quiet for awhile, but they eventually become known. They NEVER try disinformation or partial truths.
Existence of aliens? Yup, they know but say they don't and have offered all this falsified evidence to prove it.
However they couldn't do something as simple as what Timothy said to make enemies rely on GPS as much as we do and then screw it up on them when push comes to shove. Instead we let everyone use it but make the heaviest use of it ourselves so GPS jammers become a hot commodity.

The Jedi Master