I wasn't going to answer this till I saw the number of brainless "The Taliban sheltered Bin laden and refused to hand him over etc" answers. The Taliban did no such thing. They were fed up of him giving them problems, becuas they still wanted the Unocal pipeline deal to go ahead, and he was putting the whole project in danger. You do remember the Taliban leaders being invited to Texas and shown the sights in 1999, right? I don't remember there being too many voices of concern about their association with Bin Laden then. They actually arranged a deal with Pakistan for him to be tried at a council of Islamic elders in Peshawar, using any evidence the USA provided that he was involved, and if found guilty they would hand him over. The Bush administration refused the deal, partly because there was no evidence, and partly because they wanted control of Afghanistan, which is of massive strategic importance. All those various occupying powers over the years didn't invade for fun you know. That's why the USA has spent no money on rebuilding Afghansitan shattered infrastructure, apart from on the US embassy in Kabul.
The USA is the world's biggest terrorist, and has been for over half a century. Nobody since Stalin has such a proven track record of deliberately targeting civilians, which is pretty much the definition of terrorism.