As I said, weapons present a dilemma to the will of others, rebalancing a situation, hopefully in favor of the just and the true, leading to a rapid cessation of hostilities. 

Your army education must have been a hurried project.  Read up on maneuver warfare, and the concepts of putting the enemy on the horn of a dilemma, using fire, maneuver, and combined arms.  The idea is to put the enemy in a situation of rapidly diminishing options, working against their ability to see the full battlefield, and against their will to fight.    

That is to say working the tactical problem so fast they don't have time to respond to your first initiative, breaking their comms, their targeting, their ability to mass fires, via a breakdown of the collective intellect and the will.  

Speed and rapidity of execution create chaos on the other side. 

Weapons thus become - wait for it  - an instrument of a more rapid peace.