We haven't yet seen a corporation start a world war because multinationals the scale of google and samsung are a relatively recent phenomenon. With that said I

We haven't yet seen a corporation start a world war because multinationals the scale of google and samsung are a relatively recent phenomenon. With that said I agree that we're unlikely to see a world war started by a corporation. I think we're far more likely to see an interplanetary conflict started by a corporation however. It will be quite an easy thing for an asteroid mining venture to turn into an arms manufacturer the likes of which we have never seen.