Baloney

There is a lot of nonsense about the War on Terror and there are a select group of people who seek to undermine Western actions at every corner. One of the many, many tidbits of nonsense that goes around these circles is the claim that the Taliban offered Bin Laden to the U.S and the U.S rejected it. Thus, the U.S never really cared about terrorism, they just wanted to go to war with Afghanistan. Noam Chomsky is part of this school of thought, as is Gareth Porter recently writing 

The Bush refusal to negotiate with the Taliban was in effect a free pass for bin Laden and his lieutenants, because the Bush administration had no plan of its own for apprehending bin Laden in Afghanistan.

They usually cite these reports: 

After a week of debilitating strikes at targets across Afghanistan, the Taliban repeated an offer to hand over Osama bin Laden, only to be rejected by President Bush... The offer yesterday from Haji Abdul Kabir, the Taliban's deputy prime minister, to surrender Mr bin Laden if America would halt its bombing and provide evidence against the Saudi-born dissident (The Independent, 15/10/2001)

Credibility

This position is open to two sets of criticisms, both of which undermine the "offers" given by the Taliban. Firstly, the credibility of such offers is minimal for several reasons. The Taliban claimed that Bin Laden went "missing" before they then went on to offer him when faced with air strikes. The Taliban continued to speak with two voices, the highest echelons (Mullah Omar) rebuffing any indication saying in October "there was no move to hand anyone over" while the less senior officials like Muttawakil and Kabir needed "evidence" and would pass him over to a "third country" which would never "come under pressure from the United States." Even this offer is unreasonable given the British government published a dossier on Bin Laden's involvement in 9/11. 

And even this is being far too generous to the Taliban: they have a history of making "offers" which amount to nothing. The National Security Archives obtained a file which was written pre-9/11 which documents talks with the Taliban on Bin Laden:

In our talks we have stressed that UBL has murders Americans and continues to plan attack against Americans and others and that we cannot ignore this threat... These talks have been fruitless. The Taliban said that they want a solution but that cannot comply with UNSCRs [United Nations Security Council Resolutions that demand his expulsion from Afghanistan]. In October 1999 the Taliban suggested several “solutions” including a UBL trial by a panel of Islamic scholars... Taliban consistently maintained that UBL’s activities are restricted despite all evidence to the contrary. Often our discussions have been followed by Taliban declaration that no evidence exists against UBL

This all sounds very familiar but these talks did not concern 9/11 but the other attacks Bin Laden carried out against Americans pre-9/11. At this stage it should be sufficient to say that the Taliban have a track record of dilly-dallying but there's more. Evidence was consistently rejected by the Taliban: 

On May 27, in Islamabad, Undersecretary Pickering gave Taliban Deputy Foreign Minister Jalil a point-by-point outline of the information tying UBL to the 1998 embassy bombings... The Taliban subsequently rejected this evidence.

This is also the conclusion of the British government:

[In June 2001] Despite the evidence provided by the US of the responsibility of Usama Bin Laden and Al Qaida for the 1998 East Africa bombings, despite the accurately perceived threats of further atrocities, and despite the demands of the United Nations, the Taleban's regime responded by saying no evidence existed against Usama Bin Laden, and that neither he nor his network would be expelled.

Sometimes they just refused to respond to the USG (e.g. Sept. 29, 2000, October, 2000). The result is that the U.S approached the Taliban to expel Bin Laden 30 times before 9/11 to no avail. This in spite of repeated "negotiations," and demands not just from the USG but from the United Nations Security Council. Even the Bush administration tried three times in 2000 to no avail. In sum, we had multiple voices speaking out on something that the Taliban regime was clearly not serious about and had avoided. It is no surprise that the USG did not take seriously calls for evidence or negotiations: they completely lacked credibility. 

Insufficiency 

Secondly, even accepting entirely that Bin Laden would have been handed over and bought to justice; this is just simply not enough. The Bush administration had several legitimate demands and only one of them was dubiously addressed by the Taliban regime.

Bush's demands include turning over not only bin Laden, but all members of his al Qaeda network. The United States has also urged Afghanistan to close all terrorist training camps, give the U.S. access to those camps and release eight Western aid workers accused of trying to convert Muslims to Christianity. (CNN, 07/10/2001, BBC, 14/10/2001)

This was made explicitly clear by Colin Powell in his interview with NBC's Meet the Press, 12 days after 9/11:

And even if we were to get Osama bin Laden tomorrow, he showed up turned over to us, that would be good, but it would not be the end. It's his lieutenants we have to get, it's the whole network that has to be ripped up. We can't take out the head and have the tail and other parts of it laying around waiting. (Washington Post, 23/09/2001)

Whats funny about this point is that often the same people who say that Bin Laden is 'just a figurehead' or is a 'myth' that has been created by the West to fight wars are often the ones making the argument that the U.S rejected Bin Laden being handed over - and they fail to see the irony.