If you’re faced with this question — should President X have the power to impose Punishment Y on Bad Person Z? — and you answer in the affirmative based on your adoration for or trust in current President X, or your belief in the wisdom and justness of Punishment Y in the specific proposed case, or your acute scorn for Bad Person Z, you’re actually doing much more than ratifying this power in a single instance, even if that’s the limit of your intention. Whether desired or not, you’re affirming — and entrenching — the legitimacy of the principle itself, ensuring that this power will be exploited in ways you can’t control. When enshrined without checks, the endorsed punishment power will inevitably — necessarily — endure, and even grow, beyond the reign of the leader you trust to future leaders you don’t, and will be applied against not only those you believe are deserving of it but those you know are not.
— Glenn Greenwald (Salon), referring to “limitless, secret surveillance, and torture, and due-process-free and oversight-less citizen assassinations ordered in the dark, and indefinite detention, and extra-judicial killings carried out by drones”