The galaxy, and by extension the universe, is a vast place after all. For whatever happens, one would not be missed. The Imperium is already a big place by itself, containing thousands of quadrillions of people. Yes it is the worst combination of nazi Germany, USSR, medieval Europe, and various other unpleasant parts of human history. But it is either to be reduced as a tiny insignificant expendable cog in a interstellar war machine or to become cattle. Which one is worse, slave or cattle? In the galaxy of the 41st millennium, these are the only two fate for every last individual. Humanity, Tau, Eldar are all enslaved by a unforgiving system, a system of suffering and soil grinding struggle for the survival of the species. In these times, how dare the individuals have the belief that their lives mattered. Yes, the Imperium routinely kills tens of billions of its own citizens. But this is the grimdark distant future after all. It does not matter if they die or not, what does matter is that they complete their task, for no man, woman, or child died in the struggle for humanity's survival died in vain. The Eldar's plight are result of their own decadent nature, they deserved to die out, since a good portion of the galaxy's problems are their fault. They were created to be weapons of the old ones, to defeat the C'tans and their Necron servants. To ensure their master's victory and survival. Their fate was to be cast aside after the war in heaven. Like the Orks, they failed their duty, and the old ones gone extinct. The Tau are little more than naive newcomers who have no idea of the horrors that lurks amongst the stars. They think they are going to unite the Galaxy under some happy federation of greater good. Humanity tried that back in the golden age of technology, and look what were their rewards for helping out the aliens. The second that humans lost the control over their A.I constructs, the aliens turned on them. If you think the Imperium is unjust, take a look at the rest of the galaxy, and then try to defend the other races. People constantly tried to use modern western perspective to look at the Imperium, what an hypocrisy