Utopia Justifies The Means: The motivation behind any number of Renegades – usually inspired by some form of Post Historical Trauma who have plans to “bring order/freedom to the galaxy”. Reminders that the “order” in the Empire’s “Order, Progress, Liberty” motto is supposed to be emergent order, or just how very paradoxical it is to use the kind of Means which have to be Justified to bring about a shiny utopia of freedom rarely help all that much. (See also, literarily, A Good Man.)
Also the thinking behind such branches as the Sanguinary Enforcers of the Liberty Ethic, whose plan for bringing about said utopia are only slightly more nuanced – say, the mentioned branch’s “kill absolutely everyone everywhere who entertains authoritarian ideas”. Fortunately, somewhat less idealistic thinkers generally prevail.