Quick FYI: Iran is not part of the Arabic world and their language is unrelated. An Iranian friend once told me he would rather learn French than Arabic, as it would be easier for him.
The Iranians have been at odds with their Arabic neighbors for a long time and have much closer links with the people of Afghanistan, for instance. Not that that would be enlightening to most people but I thought I would mention it because many people lump Iran together with "the Arabs" since it is still part of the Middle East.