Drones hover over Paris landmarks and U.S. Embassy

I don't think that they were being used for nefarious purposes, like sourcing intended targets. Not unless they were being operated by extremely stupid terrorists. There would be no need to fly over Paris to select any targets, they only have to look on Google earth. In truth the ONLY reason (if they were terrorists and they had a smattering of intelligence)would be to fly them one time only and that is attack time. Otherwise as has been found you advertise your presence beforehand and for any budding terrorist would be the biggest and only mistake he would make in his short career.