It certainly is effective in my opinion, it is simply common sense that if a man knows something and refuses to reveal it and this information is vital to the security of the lives of the citizens of your country then if he refuses to reveal it willingly then the only option is to force him to reveal it against his will by inflicting pain on him.
As far as people telling you what you want to hear, if there is a reasonable possibilty that this man knows something it is worth it to torture him. You certainly cannot get information by offering the man something he wants for two reasons. One is that he may want something immoral, the second reason is that soldiers can be trained to resist temptation if it was only temptation and no pain. And there are ways of determining the probability of whether a man knows something or not.
It is up to you to evaluate all information which you receive, information which is obtained through torture is no exception. Information received through torture only has the added authority that this man if he knew something would be willing to do anything to end his pain and therefore was motivated to reveal what he knew.
Of course there are always innocent people, no one would advocate for the elimination of laws and courts because sometimes innocent people are punished. To advocate for such a thing is sheer foolery. Torture is the same.
I do consider it moral by the way to torture an evil person to save a child's life and I do not think that a world where torture exists would be worse than a world where children die because some person chooses not to use torture. I do not consider it an evil act because how you measure actions are by the end result not the action itself. Physical force is a fact. It is not itself evil. It is only when physical force is used to violate a persons individual rights (the right to life, liberty, property and the pursuit of happiness.) that it becomes immoral. And the same physical force when used in retaliation, in self-defense and in the defense of individual rights becomes moral.