I am not sure that Iran wants to dominate the region. It has enough internal problems, and its economy is still too weak (despite the recent spike in oil income) to allow it to control the region.

I don't expect Iran to become the dominant power in the region for a number of reasons. It is a Shiite country in a Mideast where only Iraq has a large Shiite population. It is also a Persian country in an entirely Arab Middle East. Wars between Persians and Arab recur through the history of the region.

Finally, geopolitical considerations -- and the strong US presence in Saudi Arabia, Qatar, Kuwait, and of course Iraq -- will be major obstacles to Iranian dominance.

The popular support that Iran received shortly from its neighbors after the Islamic Revolution has mostly evaporated in the last few decades. Iran's anti-American and pro-Palestinian stands are applauded in the region, but this popularity is unlikely to translate into serious strategic strength.