Short answer: Not likely. ThinkProgress has the long answer:
When it comes to Iraq, a common refrain from President Bush and other stay-the-coursers is that “if we were to leave before the job is done, the enemy would follow us here.” For example, on March 6, Bush said:
The extremists are fighting to take control of Iraq so they can establish it as a base from which to overthrow moderate governments in the region, and plan new attacks on the American people. If we fail in Iraq, the enemy will follow us home.
A new report from McClatchy debunks Bush’s claim. Here’s what the survey of military and diplomatic analysts found:
U.S. military, intelligence and diplomatic experts in Bush’s own government say the violence in Iraq is primarily a struggle for power between Shiite and Sunni Muslim Iraqis seeking to dominate their society, not a crusade by radical Sunni jihadists bent on carrying the battle to the United States.
While acknowledging that terrorists could commit a catastrophic act on U.S. soil at any time - whether U.S. forces are in Iraq or not - the likelihood that enemy combatants from Iraq might follow departing U.S. forces back to the United States is remote at best, experts say. Read more...
As Faiz notes at the end, our continued presence in Iraq and our constant mistreatment of detainees makes the likelihood of another attack greater; not less. Kinda like how George's war is creating more terrorists than it's eliminating. If there's any metric with which to measure our success in the Global War on Terror, that would be it.