Guns,cannons and other helped in the majority of conquest
They crossed the border to help fight.
It increases as they need to ship supplies to the army for medical uses or ammo such like. They need to rapidly produce weapons and ammo so that they can continue to fight on. Medicine such as penicillin was mass produced as it stopped infection rate so the mass production of that drug helped in ww2
Really hope this helps :)
The important issues was Democracy.
