Briefing: What's behind Iraq violence?

It's not strictly an Al Qaeda resurgence or a deep religious hatred: It's Syria, and it's politics.

The last U.S. combat troops left Iraq in 2011, "having succeeded in the mission of giving to the Iraqis ... a chance for a successful future," said President Obama at the time. In the past month, that future has dimmed, with the Sunni Arab insurgency flaring anew, particularly in Anbar Province. What happened?

Did Iraq's civil war really end?

No. The very day the last US troops left Iraq, Prime Minister Nouri al-Maliki, from the Shiite-Islamist Dawa Party, turned the screws on senior Sunni Arab politicians in parliament, signaling his intention to crush his political enemies. Mr. Maliki called for a vote of no confidence against Deputy Prime Minister Saleh al-Mutlaq and issued an arrest warrant for Vice President Tariq al-Hashemi, the country's most senior elected Sunni Arab officials.

In the years since, Maliki's government has worked steadily to undo whatever progress toward political reconciliation had been made prior to the US exit. While Iraq is much less violent than it had been, thousands of civilians are still being killed in political violence each year. In 2012 civilian deaths jumped 17 percent. Last year such deaths more than doubled, to more than 8,000.

What is the problem?

Spillover from the civil war in Syria is a key part of the picture. The Islamic State of Iraq (formerly Al Qaeda in Iraq) merged with Syrian jihadis to form the Islamic State of Iraq and the Levant (ISIS). Two-way traffic in weapons and fighters has flowed across the border, particularly through the Iraqi provinces of Anbar and Nineveh.

But the deeper and more important reason for the violence is Iraqi politics. Maliki has persistently targeted Sunni Arab politicians for prosecution in the past two years and has failed to deliver on promises of jobs and money that were made to Sunni Arab fighters who joined the fight against the insurgency in 2007.

When a senior Iraqi general was killed in an ISIS ambush in December, Maliki used the attack as a pretense to violently clear a Sunni Arab protest encampment in Ramadi, and arrested a senior Sunni Arab member of parliament. That sparked insurrection in Anbar, particularly in Ramadi and in Fallujah (the town where US troops fought two famously bloody battles in 2004).

Has Al Qaeda taken over Anbar?

No, it has not. The first challenge is defining "Al Qaeda." Since the moment that a group calling itself Al Qaeda in Iraq was established in the country, shortly after the US-led invasion, there's been a lot of confusion about the nature of the connection between the Sunni jihadis fighting inside the country and the original Al Qaeda led by Osama bin Laden.

Though there were ties between the two groups, the jihadis in Iraq always fought autonomously, and many in their ranks were far more focused on national aims than on Al Qaeda's sweeping Pan-Islamic vision.

But Al Qaeda's fellow travelers have seized control of Fallujah and Ramadi, correct?

Not exactly. The Sunni Arab tribes along the Euphrates River in Syria and in Iraq's Anbar Province have strong cultural and familial ties. Many Syrians flocked to Iraq to fight the United States and its allies in the area in the mid-2000s. That's a key reason that the Islamic State of Iraq was able to merge so seamlessly with Syrian jihadis. But while the group has been riding high recently, prompting Iraqi police to abandon their posts in both towns, "controlling" is something else.

Ramadi is contested. Iraqi government forces and Sunni Arab tribes that have allied with them have driven the insurgents out of part of the town. In Fallujah, the insurgents still have the upper hand but are unlikely to hold out indefinitely.

Is there any hopeful news in all of this?

Yes. Remember: Al Qaeda is its own worst enemy. During the US war in Iraq, Al Qaeda quickly wore out its welcome with the major local tribal confederations and the general public. Floggings and summary executions of locals for violating Islamic law, as well as general contempt for tribal practices and authority, saw to that. The group also threatened the economic interests of powerful figures in the region who had long controlled lucrative smuggling routes. They did not want interference from the mujahideen. That opened the door for the Sahwa, or "Awakening," in which Sunni Arab tribes took up arms against the jihadis in exchange for cash and political influence.

The same dynamics are in place today. Anbar hates and fears the central government in Baghdad since, after all, the Shiite-dominated government of Maliki has treated the region and its leaders like dirt. But many leading tribal figures don't like the jihadis, either. Maliki said Jan. 13 that he would revive the Sunni awakening, promising to give tribal fighters better salaries and to recognize them as official security forces.

So it's Sunni-Shiite hatred that's driving this, right?

The Sunni-Shiite divide in Iraq does drive much of national politics. But it's not the whole story. Intermarriage between the sects is common, most Sunnis and Shiites still list "Iraqi" as their core identity, and many of the largest tribal confederations contain both. The divide is drawn by power and money, not a dispute over the nature of Islam. Saddam Hussein's Baath Party, the backbone of his murderous secular dictatorship, was open to Shiites as well as Sunnis, and many Shiites joined up for the economic and social advantages it conferred.

This is not to say that sectarian hatred isn't real or wasn't a crucial component of the darkest days of the civil war. Sectarian death squads roamed the country in 2006 and 2007, torturing and killing people purely for their religious beliefs. In traditionally mixed cities like Baghdad, whole neighborhoods were depopulated of Sunnis and vice versa.

But much of the current hatred revolves around recent political choices. Maliki's persecution of prominent Sunni Arabs is a key reason that ISIS has such an opening in Iraq now.

The problem can be solved by the right political choices. Those choices are now Maliki's to make.