It was in the context of war zone but it's not a massive stretch of the imagination that sooner or later some terrorist movement will start using them. In fact I am surprised they haven't already.
My armchair theory is that anyone smart enough to inflict horrifying damage on society is able to find a comfortable niche for themselves within it, with a very few rare exceptions. Maybe the FBI and other agencies are more effective than we give them credit for, too, and can crack down quickly on groups with a central mastermind and expendable minions carrying out attacks
I came to a similar conclusion while standing in security queues at airports. There are heaps of easy ways to do dastardly airliner-related things but the people with the capacity are too nice to actually do anything like that and are all too busy anyway.
Assassinating public officials with drones has become a fashion. Just not in the US (yet). If you don’t think it’s on the US Secret Service’s radar though, you’re not paying attention.
A common tactic in Syria for years is literally putting a couple lbs of explosives on a consumer drone and kamikaze’ng it into a target.
Where would the most predictable time be for going after an official? At a large event they are supposed to be at.