By your logic of majority oppression the Feds could crush a population of one million if it benefited their club of trillions. Come on, what's the suffering of a million compared to the well-being of trillions of life-forms?
Every liberal democracy values the life and liberty of each individual as much as it values the common good. You do not have to formalize minority protection precisely because the basic principles of our constitutions already imply that 'the needs of the many do not outweigh the needs of the few'. Picard also says the same thing
when he talks with Dougherty. I might be a left-winger but I am also an anti-communist precisely because in the name of the common good millions had to suffer. You can help everybody without violating human rights in the process.
Once you believe that you may crush people of your society for the benefit of a majority you become a tyranny and once you believe that you may crush people of another society respectively an entire alien civilization you become an imperial power..
for the most part you're correct. But principles and rules are not absolute or they lose the effectiveness which is their actual purpose. You're applying the "don't trample on a minority" principle which is a generally good one to a rigid degree to the point that it's actually causing greater HARM by your unwillingness to bend on it.
All democracies and (just)societies are built around a balance between individual/minority rights and a "the needs of the many outweigh..." principle. In the INS scenario, the greater good simply carries the day.