See, here's the thing.
Call it what you want; "enhanced interrogation", "extraordinary measures", "psikhushka". The systematic infliction of suffering is inherently corrupting to the people who administer it and the organizations that employ it.
Because torture is not interrogation.
Interrogation is intended to gain information.
Torture is intended to gain confessions. Confessions that the torturers want to hear.
A person that uses torture to gain confessions becomes useless as an interrogator and deaf to information. The agonized babble of a person suffering beyond coherence quickly becomes meaningless noise. If you are tortured you will say anything, everything, to make the torture stop. If you are the torturer you lose the ability to find the truth amid the pain and fear.
An organization that employs torture and torturers quickly becomes a servant of the propaganda that the torture is meant to support and the presumptions that the torture is designed to confirm.
Armies that use torture begin to become instruments of that propaganda rather than instruments of policy. Intelligence agencies that use torture begin to become guardians of the secrets of and defenders of the barbarities of torture rather than cold instruments of state. Nations that use torture quickly find how useful it is in generating results that they want in the short term. And the spiral of torture, and lying to hide the torture, and lying to excuse the torture, and lying to hide and excuse the lies, works deeper and deeper into the culture of the army, and the intelligence agency, and the nation.
Until first the torturers end up running the intelligence agency.
And then the torturers become the generals.
And, finally, the torturers become the presidents and prime ministers.
The toxic "war on terror" has been the ground that has nursed this poison tree, and has given it the night and fog it needed to grow. To our shame We the People have never insisted on throwing open the doors, letting in the light that would have killed this noxious weed, never dug deep and uprooted and thrown it and the torturers on the fire. In our fear and hate we have let it grow.
If shame were still a permissible public emotion we should be ashamed of ourselves.
But we will not.
And, instead, we will nurture the fruit of that poison tree in our hands and our hearts.