In the spirit of Pascal, I apologize in advance for not having a more eloquent, concise reply, though on my part its more exhaustion and laziness rather than lack of time.
People have different definitions of what constitutes torture. There is also a legal definition of torture (which may be vague, but will be determined judicially if it comes to that). By definition, torture is against the law. As people have different definitions of what constitutes torture, some acts will meet the legal definition, while others will not even though they meets the definition held by someone else.
I happen to agree with you that "enhanced interrogation techniques" is a euphemism for torture. By defining certain acts as such, it gives proponents of using such acts a legal basis of arguing that they're not torture, whether it's ultimately justified or not.
Does that make sense? I'm not asking whether or not you agree with the distinction (which would be hard to do as I haven't defined which acts fall under either). I'm just asking whether the argument follows, that you understand why the language matters.
A similar distinction is made for killing in war and murder. Some people believe all killing is wrong and murder. That said, there's a legal distinction between the two. Which term is applied is legally important.
I'm not sure what you are saying here. Using a euphemism doesn't make torture any better.