It does when those things happening can significantly alter beyond recognition the polity concerned. General suspicion of Catholics and hostility toward mixed race peoples in the nineteenth century make taking much more of Mexico unlikely, and the circumstances surrounding Cuba would have to probably be very different too.Okay... and, theoretically, if some things in history happened in an alternate way, those things could happen, whether or not they would be good for the USA? There are very good reasons several things in history either didn't happen or almost didn't happen. That doesn't mean those things happening would be ASB.