Human robots and robot training (aka military, police, medical, fire) are still the states best assets for controlling the already present threat to the countries borders ie the population, as well as foreign countries and their array of human robots. However drones like those mentioned in this article, do not suffer from human problems like the Chinese Whispers/Telephone/transmission chain experiments in the same way humans do, they can also lie dormant outside the normal confines of a sustainable human environment, ie food, shelter, sewage, etc. If nuclear powered drone's dont exist here before 2050 or even today, I'd be very surprised considering the obviious nuclear powered subs, how the placement of land based nuclear power stations are predominantly on the edge of water bodies, like lakes and sea's. The out of sight out of mind attitude with decisions makers, as seen with sewage outlets into rivers and sea's is another example of their thinking. Air based nuclear powered drones are not out of sight or mind, excluding the nuclear powered satellites which will burn up on entry, dissipating their nuclear radiation over a wider area, hopefully not triggering any of the radiation sensors placed around various countries.

But pattern recognition is an AI's best friend, I wonder if NOAA's NDBC (https://en.wikipedia.org/wiki/National_Data_Buoy_Center) have detected anomalies over the long term when considering these are drone's in all but name, powering sites like https://magicseaweed.com/