if the fight's imminent or already on, sure. but most of the time weapons are made long before there is the anticipation of a fight.
if nation A has a weapon that lets them fight without risking their soldiers as much as nation B, nation A will always be more willing to enter armed conflict, especially against the less-endowed nation B. so the act of making a better weapon lowers the threshold for using force.
that's one big reason why drones are exceptionally effective weapon systems. surveillance and airstrikes in enemy territory are prone to being shot down and the pilots killed or taken prisoner to be used as a bargaining chip for peace, but drones aren't. the political toll of a drone being shot down is practically zero in comparison, so drone wars can continue indefinitely without domestic outcry.
