i thought it was terribly preachy. The whole movie was one big gimmick, BUT if you can get past that, then it was actually pretty decent. It wasn't really genre-specific, which keeps you off guard, and the whole indie vibe of the movie was pretty great as well, especially with such a high-profile cast.
The dilemma presented was a classic one, an amped-up version of something you can see in just about every other episode of 24 ever... but like I said, classic. I live and work in South Sudan, the newest and most wild country on earth, so making split-second decisions is part of my daily routine, and those decisions have probably saved my life a couple times in the past... so I know what I can and can't do, and there's no way in hell that I'd be able to harm a couple of kids to get to someone. Not because of any logic or morality - even if I could save a thousand more people by sacrificing 3 - but because I couldn't bring myself to do it.
Of course, there's also the argument that killing the kids will do nothing but harden the man's resolve. The THREAT of their death is more potent than their actual death. Everything up UNTIL that point would demonstrate what the interrogator's are willing to do, but if the man isn't going to fess up for his own children, then you have a choice: when a bomb goes off at the end of the day, you're either the people who stooped low enough to sadistically rob a man of his entire family, or the people who said enough is enough, and tried to pursue other means to the best of their ability.
This is not only about a movie, but a moral dilemma. I think that everything is circumstantial, but if - like in the movie - a man isn't going to bend to keep his children alive, you as an investigator have nothing more to work with. Kill the fucker so that he can never know if he was successful or not, then go out and take responsibility for your actions.