This is the third in a series of posts on Barack Obama’s Middle East dilemmas. The topic for Part I was the war on terror, and Part II was Afghanistan. Tomorrow, Part IV will cover the Israel-Palestine conflict, and Part V will be Iran. Today: Iraq.

Iraq is not stable. The “surge” didn’t work. The US-Iraq “Status of Forces Agreement” is only a piece of paper. The country is plagued with violence. Key political actors in Iraq are bolstered by paramilitary armies, including the Badr Brigade, the Mahdi Army, and the Sons of Iraq (“Awakening”) movement. Vast numbers of Iraqis are unemployed. Industry has collapsed, and basic services — electricity, water, gas, sanitation — are intermittent or nonexistent. The army and police are corrupt and infiltrated by militias, and the army’s loyalty is suspect. Most of Iraq’s political movements are backed by or have ties to one or more of Iraq’s neighbors. Baghdad is a warren of blast walls and walled-off enclaves, reeling from years of ethnic cleansing, and Iraq’s provincial capitals are rife with intrigue, with many of them — Kirkuk, Mosul, Baquba, Basra, for instance — perched at the bring of outright civil war.

That’s the Iraq that Obama is inheriting from the decider.

As president, Obama has no choice other than to follow through on the central promise of his campaign: to withdraw one to two brigades of US troops each month. The New York Times reports today that US military planners, anticipating an order from Obama, “are drawing up plans for a faster withdrawal of American troops from Iraq in anticipation that President-elect Barack Obama will reject current proposals as too slow, Pentagon and military officials said Wednesday.” That’s the first concrete sign that Obama is prepared to stand up to the generals, who’d proposed a much slower drawdown of American forces that Obama had promised in 2008.

Indeed, when it comes to Iraq, Obama is in full control. He is not bound by any agreement or plans signed by George W. Bush. He isn’t hemmed in by the three-year timetable of the Status of Forces Agreement, which calls for US forces to stay in Iraq through 2011. And he isn’t tied to any timetables sketched out by Admiral Mullen of the Joint Chiefs, General Petraues of Centcom, and General Odierno, the US commander in Iraq. He is, yes, the commander-in-chief. In that regard, the Times report is an encouraging indication that he plans to act like one.

But drawing down combat forces is only half the story.

Many critics of Obama, who suspect that the president-elect will eventually cave in to the military and to Secretary of Defense Gates, are concerned — rightfully — about Obama’s failure to say anything concrete about what might happen when all or most of the so-called combat forces are withdrawn, say, by sometime in 2010. Defining what units are “combat forces” isn’t an exact science, but by most accounts they make up roughly half of the US forces in Iraq. That still leaves something like 60,000 to 80,000 troops that are usually described as “residual” forces, to be used for one or more of the following purposes: support to the Iraqi security forces, training of the Iraqi army and police, protecting Iraq’s borders, counterterrorism, and guarding the enormous US embassy. Soon after taking office, Obama should speak concretely about what he envisions for these forces and, hopefully, announce plans to withdraw them, too, at the same time that so-called combat units get out.

Equally important, Obama needs to enunciate his policy for Iraq. As described earlier, Iraq is a seething mix of militias and “pissed off Iraqis.” Does Obama see the United States as long-term guarantor of Iraqi stability? If so, for how long? And why? What if violence escalates among Iraq’s volatile mix of political enemies and factions? What if that violence again takes the form of sectarian-based civil war, or if Iraqi Arabs and Kurds clash over Kirkuk and Mosul? In fact, renewed violence in Iraq is more likely than not. If it erupts, especially as US forces are leaving, Obama will face accusations from neoconservatives, Republicans, and the media that he is squandering the gains supposedly accomplished during the Bush-Gates “surge.” So be it. If that’s the political price he has to pay, then he must pay it. But it would minimize the damage if he articulated, now, the view that the surge did not solve Iraq’s political divisions and that, perhaps, Iraqis might end up settling their differences by force as America gets out.

Of course, there is a great deal that Obama can do to reduce the severity of the coming score-settling in Iraq. He should go to the United Nations to get its help on negotiating a national reconciliation strategy among Iraqis, with a high profile, non-American special envoy in the lead. He can launch a diplomatic surge among Iraq’s neighbors, including Iran, to persuade them to use their influence to rein in their agents, allies, and pawns inside Iraq. (For that, the United States is going to have to pay a price: Iran will want US concessions in exchange for helping to stabilize Iraq. Saudi Arabia will want the United States to adopt something like King Abdullah’s 2002 Arab peace plan for Palestine. Turkey will want American political and financial support for its agreement to allow somewhat more Kurdish autonomy than it would otherwise like. And Syria, which has influence over Baathist and Arab nationalist forces in Iraq, will want US support for its efforts to reclaim the Golan Heights and for the United States to acknowledge its legitimate interests in Lebanon.)

There’s more: lots of US money for rebuilding Iraq. A promise not to seek bases for US forces. A willingness to allow Russia, China, Japan, and Europe equal access to Iraqi oil contracts and reconstruction efforts.

The wild card, of course, is Iran. I’ll deal with Iran, and its influence in Iraq, in Part V of this series, on Saturday.