How much of our labor is being used on activities that improve society's ability to defend itself, even in an indirect way? Isn't most of it being used to, as a schematic, serve coffee and send email?

Waste is abound, but how would you get members of the society to feel like things are "fair enough" if everyone didn't "have to work"? (they are obviously not currently, but I am referring to a more ideal society where obviously some people need to do some work)