Machiavelli wrote The Prince just over 500 years ago (it was published some years later, but written in 1505). Long story short: the ends justify the means, or at least Renaissance-era Italian princes believed so, resulting in the moral certainty of their brutal actions to bring about a "better" state when all was said and done. Here we stand, over 500 years later, watching grown men in all their wisdom vying for the right to lead the free world saying, almost to a man, that the end justifies the means, even when specifically referring to the means of torturing people. I must disagree, as must all civilized people. Beyond the obvious question of "what if they really don't know anything more than they're telling you?", people in positions of authority must be above moral reproach. Especially people who are leaders of a nation trying to set an example of being the shining beacon of hope and goodness for the rest of the world to aspire to become (and if the rest of the world doesn't see it that way, by golly, we'll MAKE 'em!). Very simply, we must do what's right and strive to achieve desired outcomes through methods that are recognized by all people as civilized and just.
But what, you say, what of the case where we can prevent the loss of innocent lives (presumably at the expense of other, different, fewer innocent or not-so-innocent lives)? For example, dropping atomic bombs on 2 Japanese cities to end WWII and spare potentially a million invasion casualties at the expense of a mere 100,000 civilians incinerated by the splitting of atoms in their close proximity. Again, the answer is simple: find a better way. Would you drop the bombs on 2 American cities to end the war, killing 100,000 American civilians in order to save a million invasion casualties? Of course not. So it's not just about the numeric trade off, with 100,000 being less than, and therefore more desirable than, a million lost lives. It's about "they are the enemy and therefore are more deserving of death than us." Yet they were fathers, mothers, sons, and daughters, going about their daily lives, and then BLAM!
Were those means justified by the ends? No. People gave up trying to find a better way and apologized later. That's clearly and plainly never an acceptable course, to do something wrong in hopes that a desired outcome of that wrong action will somehow vindicate it. It was wrong 500 years ago, it is wrong today, and it will be wrong 500 years from now, when we're still operating under the same barbaric, uncivilized, unenlightened logic of primitive, murderous, and warlike intellect.