The fibreglass lifting body immediately makes it more than your basic drone. Granted it's not exactly rocket science, but you still need to get the shape right, make a giant mandrel, fit all those panels and doors together nicely. And then you need to figure out a production line that makes it cheap enough to mass produce them -- after all, they get exploded.

Just imagine they used all of those tools and skills to make sailboats instead. Or still in the drone form-factor, have them circle events with a 5g cell relay on them or something. War sucks but it pays salaries, sadly.