What's the problem? Repression done right just means that a particular political system/approach/technique produces the desired results without the costs (including secondary effects and externalities) being too high. Moral outrage is not a particularly useful analysis tool.
Just like the best war is the one your enemy has lost before even realizing he's at war, the best repression is the one where the repressed population believes itself to be happy and in control :-/
My point was that "right" is a problematic term in this case. Using less loaded terms, you're describing "effective" or "successful" repression.
So, back to the original argument:
VoiceOfRa claims that [effective] repression doesn't cause rebellions. You seem to agree with me that it's mostly because the dead don't complain. Indeed, it's not very effective; if removing dissenters is your solution to everything, you'll end up a lonely tyrant.
Here's my op-ed that uses long-term orientation, probabilistic thinking, numeracy, consider the alternative, reaching our actual goals, avoiding intuitive emotional reactions and attention bias, and other rationality techniques to suggest more rational responses to the Paris attacks and the ISIS threat. It's published in the Sunday edition of The Plain Dealer, a major newspaper (16th in the US). This is part of my broader project, Intentional Insights, of conveying rational thinking, including about politics, to a broad audience to raise the sanity waterline.