Al Qaeda has made it clear that it is now determined to regain control of parts of the country that it lost in 2007-8. Terrorism deaths have increased since the last American troops left at the end of 2011, and so far the Shia controlled government, and the Shia majority, have not retaliated against the Sunni Arab minority. There are still armed Shia militias that are willing to resume their use of death squads to drive Sunni Arabs out of their neighborhoods or even out of Iraq.
There is a Sunni Arab majority in thinly populated western Iraq (Anbar province), and these would be difficult to drive out. The tribes out there have branches in Jordan, Syria, and Saudi Arabia and have called on those foreigners for help in the past and received it. The more radical Iraqi Sunni Arabs have long sought to generate enough violence by killing Shia and provoking Shia death squads to strike back in order to force neighboring Sunni states to invade Iraq. That failed in 2007, when the U.S. persuaded most Sunni Arabs to back the Shia dominated government and that government was able to shut down the Shia militias and their death squads.
The Sunni terrorists are pushing this plan again because last time there were over 100,000 U.S. troops in the country and Sunni Arab neighbors were not going to overcome that to take down the Shia death squads and the Shia Iraqi government. This time the American troops are gone (although there are several thousand former U.S. military personnel working as trainers or security operatives). The Sunni Arab plan is still flawed, mainly because of the growing hostility between Shia Iran and the oil-rich Sunni Arab states across the Gulf. These nations are mostly a majority of Sunni. The United States is the most powerful ally these Sunni states have and they are not interested in driving the Americans out. Not with Iran on the brink of obtaining nuclear weapons.
The Iraqi Sunni Arab terrorists see themselves as champions of righteous Sunni Islam against Shia heretics. Iran, as self-appointed head of the Shia (and the largest Shia majority nation) sees itself as the leader of a movement to reestablish the Shia form of Islam as the dominant one. This would mean converting (with force if necessary) over half a billion Sunni Moslems. Currently, about ten percent of Moslems are Shia and over 80 percent are Sunni.
This animosity between Sunni and Shia has festered for centuries but now al Qaeda and Iran are pressing for a violent resolution. Most Sunnis and Shia are not interested in yet another war over the matter (there have been several in the past). There is also the ethnic issue. The Iranians (along with the Kurds) are Indo-European people who have long despised and mistreated the Arabs. Now the Arabs have oil wealth and powerful allies and less fear of being rolled over by the Iranians. It's a dangerous situation and Iraq is still ground zero.
Iraq's Sunni neighbors (including Turkey) have condemned the recent surge in Sunni terror attacks against Shia. The Turks have centuries of experience dealing with this, as well as an often hostile Shia Iran on the eastern border of the Ottoman Turkish Empire. While the empire is long gone (dissolved in 1918, after World War I), memories of the constant strife between Sunni and Shia are still there. The Sunni Arab neighbors of Iraq, particularly Saudi Arabia, want to maintain Arab unity against Iran. But on the ground ancient Sunni hatred for Shia still survives and often thrives because of radical clerics.
Iran continues to contribute cash and technical specialists to Shia Islamic radical groups in Iraq. This turns religious schools into training centers for Islamic terrorists. The Iraqi government is reluctant to crack down on this because some of the schools are approved by prominent Shia clerics.
Sixteen percent of all terrorist attacks last year occurred in Iraq. Another 69 percent of these attacks occurred in Afghanistan and Pakistan. Most of the victims, and nearly all the perpetrators, were Moslem.
