I don't doubt the US was happy to go to war (and do doubt Bin Laden would have gone quietly if the Taliban had said "you're welcome to come and arrest him") but it's something of a stretch to imagine Afghanistan only wanted to "see some proof" even if that was one of their stated positions.

The Taliban had spent the last three years refusing multiple countries' requests to extradite Bin Laden for other bombings and was lead by a man married to one of Bin Laden's daughters who compared the notion of handing over Bin Laden as a betrayal akin to the "end of Islam"