It's been happening for years according to Wiki! And there are at least 2 military projects that seem to be in the public domain regarding it. Not sure what the issue is myself.
The US Military have been doing it for years - watch The Men Who Stare at Goats as conclusive proof!
They are not doing a very good job though, based on what happened in the US yesterday. Or was the disruption to the Bears v Ravens game deliberate?!