I would say the Iraq war planted the seeds for the arab spring. The high unemployment, high food costs was the water that made it grow.
The idea's that were spread from the Iraq War and proceding years as governments were formed and elections had reverberated throughout the arab world. The ideas were thus; You don't HAVE to have a dictator, you don't HAVE to be undemocratic, you CAN have a say. It was exemplified with what happened in Iraq and the people saw this and carried this forward in their countries.