It's probably a lot more prosaic than I imagine.
It happened 175 days ago, when you made an unwise comment about killing children. All your comments since then have not been visible, or upvotable. This is why you're supposed to put contact information in your profile.
I hesitated before posting this, since from your older comments you appear to be a bit of a reddit user, and the comment itself contains several significant technical errors regarding the design of nuclear weapons, (American nuclear weapons haven't been of the "gun" type for 60 years now) which casts a poor light on the comment as a whole; but I don't think you're completely beyond hope.
Make a new account. Try not to be an asshole with it.
But the post was killed...
The reason they don't use GPS is that you would (hopefully) only start throwing ICBMs around if you are in "nucular combat toe to toe with the Rooskies" - and the way you know you are in a proper war is that all your GPS satellites have just been destroyed by the other side.