You got it all wrong. You build your military so you can siphon tax payer dollars into military contracts given to your friends.

Then you ask your rich politician friends in "enemy" countries to do the same with their tax payer's money, and you agree to threaten each other once in a while to justify your ever increasing military budget to the people you are basically stealing from.

And if you're really on a roll, you can invade countries that are no match for your military and plunder their resources on the pretext that they harbor terrorists or WMD's, but only after conducting an effective psyops operation.

That's why you build up your military.

You're welcome.