What is the historical significance of torture? How does it relate to the World Wars?
Here is the definition of torture according to the United Nations Convention Against Torture:
...any act by which severe pain or suffering, whether physical or mental, is intentionally inflicted on a person for such purposes as obtaining from him, or a third person, information or a confession, punishing him for an act he or a third person has committed or is suspected of having committed, or intimidating or coercing him or a third person, or for any reason based on discrimination of any kind, when such pain or suffering is inflicted by or at the instigation of or with the consent or acquiescence of a public official or other person acting in an official capacity. It does not include pain or suffering arising only from, inherent in, or incidental to, lawful sanctions.
I know that waterboarding was a form of torture that was used during World War II by the Japanese and the Gestapo. Waterboarding is when a person is lying on their back (immobilized) with a cloth over their face. Water was poured onto the cloth which then entered their sinus cavities. It gives the person the sensation of drowning. They were also usually beaten during the process so every time they would open their mouths to speak or scream they would take in water.