Do you think the labor and resources that went into creating that materiel would vanish if it wasn't created? Like a missile is magic and conjures engineers and metal into existence just to fulfil its creation?
Oh and in fact leaves a little left over, the "profit", because thankyou for giving it some schools to obliterate?
What would we do if we weren't blowing people to bits huh, building theme parks or something instead - oh the waste! Think of the ~slaughter~... ahem, I mean the "economy"!