Wrong. The toy doesn't promote violent behavior, it responds to the fact that little boys, like grown men, have aggressive impulses.
You could put a thousand Barbies in a room with typical little boys, and it wouldn't "promote" feminine qualities in them. Within a few minutes, the boys would be happily bashing each other the head with the dolls, building skyscrapers with them and delighting in knocking them down, etc.
Our behavior lies in our genes, not in our toys.