"The National Commission on Terrorist Attacks Upon the United States (also known as the 9-11 Commission), an independent, bipartisan commission created by congressional legislation and the signature of President George W. Bush in late 2002, is chartered to prepare a full and complete account of the circumstances surrounding the September 11, 2001 terrorist attacks, including preparedness for and the immediate response to the attacks. The Commission is also mandated to provide recommendations designed to guard against future attacks."

I would certainly say being, "chartered to prepare a full and complete account of the circumstances surrounding the September 11, 2001 terrorist attacks, including preparedness for and the immediate response to the attacks", puts Iraq well outside their remit considering the timescale.

As to the reasons offered for including "Iraq" factors, one is valid, the other is not. Valid - extension of the war against terror - falls into measures taken to prevent potential future attack. Invalid - that resources were taken away from the Afghan theatre of operations - they weren't, the US currently has around 15,500 troops stationed in Afghanistan engaged in operations against Taleban and Al-Qaeda.

The new Afghan interim government were very specific when it came to what troops could remain and what their functions would be. The Pakistani Government even more so. There was no way on earth that they would allow foreign troops to operate in "hot pursuit" operations over the Afghan border into the tribal areas of Pakistan, since the time of partition in 1947 sucessive Pakistani Governments have adopted a policy of non-interference in those areas. The reality of the situation is that if troops have to be deployed in those areas, they have to be Pakistani troops acting on the orders of the Pakistani Government.