At the blog Overthinking It, a delightful roundtable has assembled to overthink the economics of the Death Star, as seen in Star Wars. In case you don't recall, the Death Star was a weapon designed to destroy an entire planet -- which brings up some potential issues if that planet is a productive part of an empire (sorry, Empire). The initial question boils down to:
Doesn’t the Empire take a huge economic loss from the lost productivity of an entire planet? They were presumably paying taxes and providing resources to the rest of the Empire. Presumably the loss of that planet’s output would have to be made up by increased output from other planets that were either slacking in productivity due to rebellion or threatening to rebel and withdraw from the Empire altogether. It doesn’t seem to make good economic sense.
From there, the discussion veers into Roman history, the use of nuclear bombs in World War II, the general economics of war, bureaucracy, republics, and so on. It's actually very enlightening, and I encourage you to geek out on this, assuming your Midi-chlorian count is sufficiently high.