I'm new here, but I'll take a stab at it. The Fithp are obligate herbivores, with a herd mentality much like that of large Earth herbivores such as horses and buffalo. (Although they look somewhat like elephants, their social structure isn't much like that of elephants. For one thing, males are part of it.)
Most herd animals have evolved a surrender reflex; part of the reason is that combat between large animals with natural weapons for dominance is risky for both. If the dominance relations are essentially settled, then combat is less likely and at least one of them is more likely to have offspring.
The political structure is essentially "herds writ large" - presumably with sub-herds forming when the population gets big enough.
Compare and contrast humans, who don't have significant natural weapons and are also evolved from creatures (somewhat similar to modern-day chimps) which don't either. As a result, our dominance relationships have always been more fluid because we could afford to fight. Of course, that advantage went south when we developed weapons - but our instincts have not evolved so far yet, perhaps.
