The 2003 Iraq War: Operations, Causes, and Consequences
The conflicts in Syria and Iraq have attracted foreign fighters by the thousands. Middle Eastern and Western intelligence agencies have raised concern that their citizens who have joined the fighting in Iraq and Syria will return to their home countries to carry out attacks. Director of National Intelligence James Clapper estimated in February 2015 that more than thirteen thousand foreign fighters joined Sunni Arab antigovernment extremist groups, including the Islamic State, in Syria, and that more than 3,400 of more than twenty thousand foreign Sunni militants hailed from Western countries. ( Estimates of the group’s total forces have ranged from around thirty thousand to more than a hundred thousand; . special envoy Brett McGurk said in June 2016 congressional testimony that the group comprised some eighteen to twenty-two thousand fighters, down from a high of thirty-three thousand in 2014.)
So when the US began dropping hints that Australia provide an armoured reconnaissance unit – made up of light armoured vehicles – to help protect the 1st Marine Division’s western flank as it drove to Baghdad, Australia baulked.
Despite the Bush administration's stated interest in liberating Iraq, little formal movement towards an invasion occurred until the September 11 attacks . For example, the administration prepared Operation Desert Badger to respond aggressively if any Air Force pilot was shot down while flying over Iraq, but this did not happen. Secretary of Defense Donald Rumsfeld dismissed National Security Agency (NSA) intercept data available by midday of the 11th that pointed to al-Qaeda 's culpability, and by mid-afternoon ordered the Pentagon to prepare plans for attacking Iraq.  According to aides who were with him in the National Military Command Center on that day, Rumsfeld asked for: "best info fast. Judge whether good enough hit Saddam Hussein at same time. Not only Osama bin Laden ."  A memo written by Rumsfeld in November 2001 considers an Iraq war.  The rationale for invading Iraq as a response to 9/11 has been widely questioned, as there was no cooperation between Saddam Hussein and al-Qaeda .