Writing a story associated with the real world is complicated, and it becomes more complicated the more closely associated with the present real world it is.
DUNE Review
Ultra-tough, misunderstood desert cultures can be a slightly overused trope in fantasy writing, especially alternative world fantasy. They often crop up as the much-needed army for the beset hero, at just the right time, after the hero properly impresses them and meets some ancient prophecy. It might be that the origin of this tendency lies with DUNE.
IGC Publishing 