You know, this is really kind of a impossible scenario. IF a terrorist was caught, and there was credible evidence that a WMD was going to go off in the next 48 hours and you thought that person knew about it, what is to stop them from lying to you for the next 48 hours and delaying the investigation to buy time so that the WMD would go off?
Putting a time limit on it is kinda screwy, because there are a lot of terrorists out there who would be able to hold out for a couple of days of waterboarding. I mean, there were several at GTMO that had it done to them over a month, and it never yielded any credible information.
However......................sugar free cookies seemed to work pretty well, and no waterboarding required.
Ali Soufan Interviewed: After Waterboarding: How to Make Terrorists Talk? | The Soufan Group
he most successful interrogation of an Al-Qaeda operative by U.S. officials required no sleep deprivation, no slapping or “walling” and no waterboarding. All it took to soften up Abu Jandal, who had been closer to Osama bin Laden than any other terrorist ever captured, was a handful of sugar-free cookies.
Abu Jandal had been in a Yemeni prison for nearly a year when Ali Soufan of the FBI and Robert McFadden of the Naval Criminal Investigative Service arrived to interrogate him in the week after 9/11. Although there was already evidence that al-Qaeda was behind the attacks, American authorities needed conclusive proof, not least to satisfy skeptics like Pakistani President Pervez Musharraf, whose support was essential for any action against the terrorist organization. U.S. intelligence agencies also needed a better understanding of al-Qaeda’s structure and leadership. Abu Jandal was the perfect source: the Yemeni who grew up in Saudi Arabia had been bin Laden’s chief bodyguard, trusted not only to protect him but also to put a bullet in his head rather than let him be captured. (See pictures of do-it-yourself waterboarding attempts.)