The results of the 8 year war are now in.
Iraq and Iran fought an 8 year war in the 1980's during Saddam Hussein's reign, which ended as a stalemate that cost a million male lives and left a population composed of a majority of women in Iran.
The U.S. backed Saddam Hussein in that war.
When the luv affair with Hussein ended after he invaded Kuwait, and the U.S. later invaded Iraq during Bush II, things began to change.
The Shia radicals who had been expatriated to Iran and elsewhere became activated and they returned to Iraq.
Soon they embedded themselves into the Iraqi government when the Baathists were banned, during the Bremer leadership, soon after the U.S. invasion and at the beginning of the U.S. occupation of Iraq.
Bremer, like Bush II, knew nothing of the Shia v. Sunni dynamics and the religious struggle between them so he, like most Americans, had no idea what was going on in that regard.
Today and back then the Shia of Iraq and Iran are aligned against the Iraqi and Saudi Sunni, and the Kurds to the north care not a lot for either; hence the U.S. has sown the seeds for the future political crop which will not be and is not now pro-American.
The Iraqi April 30 celebrations about the Americans leaving can be compared to the U.S. 4th of July alignment against the British Empire and for U.S. independence from Britain long, long ago.
Nationalism held the U.S. together then, after its independence, and will hold Iraq together for awhile now, but so will closer ties to Iran mixed with a hatred of America they now share.
These types of energies too, however, will wane eventually and those ancient divisions within Iraq will sprout once again, helping the greater problems to return to the surface and blossom.
Shia, Sunni, and Kurd will march again with Shia support from Iran, and with Sunni support from other neighbouring countries.
The U.S. civil war took a long time to develop following the exuberant 4th of July, but it came, and the April 30th Iraqi exuberance will also give way to Iraqi civil war in due time.
But it will not be as bad as the U.S. civil war was.
From an oil baron perspective, all that remains to be seen is whether the oil barons can keep a hold on the Iraqi oil they greedily went for under the oil baron regime of Bush II.