Why not go after Osama bin Laden?

I've seen it suggested here and there that the U.S. would be better off pulling out of Iraq and going after Osama bin Laden. Trouble is, bin Laden is probably spending most of his time in Pakistan.

Pakistan isn't really wild about allowing the U.S. military to operate within its borders.

PAKISTAN said it could not accept "indiscriminate action" on its territory by US forces without first being informed that there was an al-Qaeda or terrorist target there.

“We remain determined not to allow al-Qaeda or any other terrorist entity to establish a safe haven on our territory,” Pakistani Foreign Ministry spokeswoman Tasnim Aslam said.

“Whatever counter-terrorism action is to be taken inside Pakistan, it will be taken by our own security forces.”

(the Australian)

Any other great ideas?