By Mark Willen, Senior Political Editor April 24, 2009 A full-scale inquiry into the interrogation techniques used against suspected terrorists (Who did what? Who ordered what? Did it work? Was it the right thing to do? If not, who could or should have stopped it? Should anybody be prosecuted? -- the whole shebang, in other words) now seems inevitable. I think that's a real mistake, a waste of valuable time that will surely inflame rhetoric and partisanship and make it harder to tackle pressing problems, but it's beginning to look like I've been overruled.President Obama has repeatedly said he has more pressing things to do than look backwards, that it was enough for him to change interrogation procedures and not launch a vindictive probe of possible wrongdoing. His argument is a good one, and I wish he'd stuck to it, but instead he reversed himself Tuesday, leaving the door open to an inquiry and to the possible prosecution of those who wrote memos authorizing the harsh techniques, though not those who carried them out. That led to a flurry of just what we didn't need -- heated arguments on both sides. In his latest move, Obama told congressional leaders yesterday that he's again turned back against an inquiry, but the pressure to hold one is growing. I hope he sticks to his position this time so we avoid an inquiry, but if we can't, let's at least do it right and minimize the damage. A few observations: The memos: The release of the Justice Department memos has sparked a huge debate over whether waterboarding and other techniques produced useful information, with former Bush aides and opponents of the policy taking radically different views. Let's realize that we'll never know because no black-and-white answer is possible. Obama's own intelligence czar, Dennis Blair, says the interrogations produced valuable intelligence but that the damage to the U.S. outweighed the value. The problem is we don't know if we would have gotten the same information with less harsh techniques. And we don't know how many lies were offered up, just to stop the pain, that hurt the U.S. cause. Consider for a second that the American journalist accused of spying by Iran confessed under stressful questioning. No one in the U.S. believes she told the truth so how can we turn around and say suspected terrorists told the truth under what was presumably much greater physical duress? Advertisement Trust. If we're going to have a probe, it can't be run by Congress. It has to be a bipartisan independent commission run by people with impeccable credentials, similar to the 9/11 commission (though this subject is more loaded). I once thought John McCain fit the bill and he probably does in many ways, but I think it's better to keep sitting members of Congress out of it. My new choices for co-chairmen are former Sens. John Warner (R-Va.) and Sam Nunn (D-Ga.). Also possible, former Defense Secretaries William Cohen and William Perry. Whoever heads it should get plenty of support from retired generals. And give them plenty of time so the rest of us can focus on more immediate problems. Prosecutions. This can is packed with worms (snakes really). I don't see how you can prosecute Justice Department memo writers, if it comes to that, without prosecuting those who told them to write the memos and those who carried out the interrogations. Yet, both of those groups are off limits. Precedent holds that "following orders" is not an acceptable defense, but putting interrogators on trial would devastate ongoing anti-terror efforts. And accusing Bush and Cheney would rip the country in half. In any event, it'll be pretty hard to make a case against the lawyers who wrote the memos. There's really no legal precedent, experts say, for prosecuting lawyers who give bad advice.