Saw an interesting piece on this where it was claimed there have been long founded fears of a nuclear terrorist attack, where components are smuggled into the US over a period of time and then assembled to create a weapon. A mayor in New York has claimed that radioactive material has gone missing from a shipment to the US in early December, he believe that the drones are searching for this and the Government obviously can't make this public. He states that there is evidence of the drones moving in a grid like formation.
While it sounds far fetched it would explain a lot and seems a lot more plausable that little green men visiting. It seems people are now accepting this is something the powers that be are fully aware of but are keeping a lid on it for some reason.
