War is destructive enough to make it all not worth it.
That's its job.
Excess preparation for war is resource distribution, with variable effects on perceived prosperity.
Stockpiling guns & ammo costs many people a lot but others make their money this way.
Not as much as actually deploying or fully waging a war though.
With military discipline and strategy another problem comes when the myth is perpetuated about this being the strongest form of discipline and best approach to overcoming objectives in other challenging pursuits.
The complete faultiness of a military-style chain-of-command for non-military purposes is often overlooked simply because when such a visible chain is in place aboard something like a corporation, it is recognizable and familiar.
Too bad.
If you want to get the most out of your resources you're going to need a lot stronger and more effective discipline than the military, and a whole lot different style chain-of-command, from top to bottom.
Preparing for exponential growth requires a naturally different mindset compared to preparing for exponential mutual destruction.