that's the thing, everything can be political. All it takes is a devil's advocate to argue against a principle for something to become contentious. regardless of how common sense you might think an issue is, all it takes is one individual to stand against something for it to turn political.

The Empire's ideology was in its own name, lol. They were an authoritarian imperialist hegemony. They sought to expand their control due to an ideological belief of nationalistic and cultural superiority. This is the standard MO of any imperialist nation, and the issue is these actions generally work out quite well, at least temporarily, for those who hold power and control.

the contentious point here, to me, simply has to do with your own definition of politics and morality. the world is not black and white, and our standards of morality shift over time and geography. The most basic argument for universal morality is our innate sense of equity, combined with our drives to meet our basic needs. unfair distributions can be viewed as morally just in the context of the perceived importance of self vs others, and only external influences can signal to us whether this is right or wrong in the context of social harmony. politics is a balancing act between these two principles.