The Taliban and Al Quita (sp) aren't the same thing
Osama bin Laden's group is Al Quita (however it is spelled). The Taliban was the group formerly in charge of Afghanistan. Osama supported the Taliban and they returned the favor but they were separate organizations. We took out the Taliban because they were giving support to Al Quita by offering them safe haven in Afghanistan.
There is a great deal of evidence that Osama's group was behind most of those terrorist attacks. They fully admitted the Kobar Towers attacks, the African embassy attacks, the USS Cole attack, and the 9-11 attacks. Only people whose idea of reality comes from conspiracy wonk websites have trouble accepting those admissions.