I can't even think of any FReeper who espoused that view, it's so extreme. Like I said, it's not even held by most big-L Libertarians.
Right after 9/11, it wasn't clear who had done the attack. The highjackers certainly didn't leave a manifesto saying who they were, what group they belonged to, and why they did the attack! Many of them used false identities, for crying out loud.
Further, there were indications by the Taliban that they might be willing to turn Osama bin Laden over for trial. They wanted to put on a lot of unacceptable conditions, which of course the U.S. was right to reject. But they also wanted evidence...which is quite reasonable, given that turning bin Laden over was a certain death sentence.
The U.S. never really provided any solid evidence...until the slam-dunk tape, of course. President Bush said, "We know he's guilty" but never provided evidence to show why "we" knew he was guilty. (The President certainly wasn't speaking for ME when he said that...I don't know people are guilty until I see convincing evidence. Preferably a "guilty" verdict in a court of law.)