Where am I?

I've been experimenting with GPS - doing my homework for the DeFT project, and I must say I've always been impressed with the whole concept. I think I first heard of it in connection with marine navigation. The idea that satellites might replace the compass, map and chart, or the night sky as ways of plotting a journey is interesting in itself. More modern magic. I've been rather dimly aware that there are 2 sides to the GPS coin - track and trace. Not only can I see where I'm going, other people can see where I'm going, too. But who exactly? In idle moment I found myself reading the manual, the small print as you might say. There I learnt, what I assume most people already know, that GPS is owned and maintained by the US government. That's interesting, and I expect those social geographers have written all about the topic. Anyway, I'm sure there are checks and balances, I hope so. That a government might one day change the map would be nothing new, but that our position on the landscape and our direction of movement might be modified is a chilling prospect. Overnight respect for friends who pursue the noble art of orienteering has increased!