It struck me recently how vulnerable we are to small disrutpive attacks of the sort you mention, and more. For example, several major European airports were cl

It struck me recently how vulnerable we are to small disrutpive attacks of the sort you mention, and more. For example, several major European airports were closed recently due to unidentified drone activity around them. I don't know if the authorities have figured it out, but in theory someone could cripple air travel for the cost of a few anonymous drones.