[The Might]

So then, tell me, in what way are the Haradrim or the Variags different? Incapable of making lasting alliances? Why, is it in their blood, in their genes, is there anything about them that makes them incapable to act like the Rohirrim and the Gondorians?

Sorry for my indeed blunt response, but when I see no proof at all for your speculation of them being different I speculate myself.

And as I said, stop putting an equal sign between M-e and our world. Yes, Tolkien said something about us being in the Seventh Age and some British seaman having ended up in Aman and having talked to Pengolodh and other Elves. But let's be serious, Arda is not the Earth, the histories are different, we are talking about a fantasy world. And so why should Gondor and Rohan be an exception? Just because it happened to work out properly, what about alliances between Elves and Men in the First Age. They all worked out, except the one with the Easterlings unfortunately. Same goes for those between Elves, except for the Children of Feanor.

Why is it so difficult to accept that maybe in M-e alliances between good people turned out right and could stay that way. Only because in our world that was not the case? Doesn't Tolkien maybe want to teach us a lesson here, that alliances for good are possible and desirable and can last? Or is he pointing out that M-e is just as common and plain as our world?