Grand strategy, according to John Boyd (arguably America's best military strategist), is a quest to isolate your enemy's (a nation-state or a global terrorist network) thinking processes from connections to the external/reference environment. This process of isolation is essentially the imposition of insanity on a group. To wit: any organism that operates without reference to external stimuli (the real world), falls into a destructive cycle of false internal dialogues. These corrupt internal dialogues eventually cause dissolution and defeat.
Therefore dynamic of Boyd's grand strategy is to isolate your enemy across three essential spheres (physical, mental, and moral), while at the same time improving your connectivity across those same spheres.
In short, a primary objective of US grand strategy should be to increase its connectivity within the moral sphere. The embrace of torture does exactly the opposite. It self-inflicts moral isolation on the US by violating codes of conduct we profess to uphold.