You said:
"My whole point of being annoying about this is that his essay points out a truth of our existence on this planet. That groups of humans struggle for dominance and that is the way it has to be."
That's the nature of the beast at any level. I think the difference is our "dominance" is a dominance that permits an individual to think or do pretty much what he wants (within societal limits established as laws). Opportunity dominance, if you will. Other systems of government and society don't like or want that (see WWII and Hitler or any number of current demagogues).
Our republic is different. In a sense, our message is "Knock off the foolishness and let's make some money." And the individual has an opportunity to share in that.
Groups struggling for dominance within our republic could be call political parties, among others. We manage to hold our elections without warfare, for the most part. And we don't impose our system on others without provocation or reason. We left governments in Europe pretty much the way they were after WWII (active monarchies remained and republics like Germany restored). We didn't arbitrarily impose our system on everyone. I don't think Churchill would make that distinction.