I think a more accurate description would be "a type of tool created with the intent to harm". You can use your kitchen knife to stab someone, but it's not its

I think a more accurate description would be "a type of tool created with the intent to harm". You can use your kitchen knife to stab someone, but it's not its main purpose. Rifles and bombs don't kill people by themselves either, but are a damn good indication of intent and their simple presence facilitates dangerous situations.