Does the Supreme Court's Guantanamo decision mean an end to torture?

Marty Lederman at SCOTUSblog says the decision means that the Bush Administration's use of torture is illegal. See here:

This almost certainly means that the CIA's interrogation regime is unlawful, and indeed, that many techniques the Administation has been using, such as waterboarding and hypothermia (and others) violate the War Crimes Act (because violations of Common Article 3 are deemed war crimes).

If I'm right about this, it's enormously significant.

Now, that's an understatement.

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