So did the guy who invented the machine-gun, and you see how that turned out.
Richard Gatling invented the Gatling Gun for the purpose of making large wars obsolete....
"It occurred to me that if I could invent a machine - a gun - which could by its rapidity of fire, enable one man to do as much battle duty as a hundred, that it would, to a large extent supersede the necessity of large armies, and consequently, exposure to battle and disease [would] be greatly diminished.
Hiram Maxim invented the machine gun for pure profit

"In 1882 I was in Vienna, where I met an American whom I had known in the States. He said: 'Hang your chemistry and electricity! If you want to make a pile of money, invent something that will enable these Europeans to cut each others' throats with greater facility' "