Quoted in "Standard Operating Procedure"

Happy are those who died without ever having had to ask themselves: "If they tear out my fingernails, will I talk?" But even happier are others, barely out of their childhood, who have not had to ask themselves that other question: "If my friends, fellow soldiers, and leaders tear out an enemy's fingernails in my presence, what will I do?"

Jean-Paul Sartre

... though it would be interesting to know upon what basis Sartre would deem such an action morally unacceptable.