Two years after the United States pulled its forces out of Iraq, the country is, in the words of one analyst, "a house of cards."
"It is a contraption held together solely by the reluctance of its many components to let things again come to blows, and which survives on constant infusions of cash thanks to high international oil prices," wrote International Crisis Group analyst Joost Hilterman.
Yet the blows keep coming. In some parts of the country, violence has reached urgent proportions, with nearly 1,000 people killed in October alone, according to the United Nations.
With Prime Minister Nuri al-Maliki in Washington to plead for help from the United States in battling a resurgent al Qaeda, here's a look at some of the main issues facing the country.
At the heart of so many of Iraq's many problems is the deep-seated division between the country's Shiite majority and its Sunni minority.
Those divisions have deep roots, including decades of repressive and often violent policies -- particularly against Kurdish Sunnis -- under the decades-long rule of dictator Saddam Hussein, deposed in the 2003 U.S. invasion of Iraq.
A Kurdish Sunni, Jalal Talabani, is Iraq's president. However, many members of the faith feel marginalized by the more powerful al-Maliki and what the International Crisis Group described in August as his "divide-and-conquer strategy that has neutered any credible Sunni Arab leadership."
Despite a power-sharing agreement reached in 2010, Sunnis -- who enjoyed political dominance under Hussein -- have complained that al-Maliki has used "de-baathification" as a pretext to exclude them any significant role in national government.
In 2010, many Sunnis boycotted parliamentary elections after a government commission banned nearly 500 candidates for alleged links to the Sunni-dominated Baath Party once led by Hussein.
The violence playing out today has immediate roots in a 2012 Sunni protest movement that analysts say began peacefully but escalated into violence after the government responded with force first.
Only later did the government offer what the International Crisis Group described as "half-hearted, belated concessions" that did more to disillusion Sunnis than placate them.
Circumstances are likely to continue to worsen, warned the International Crisis Group.
"Under intensifying pressure from government forces and with dwindling faith in a political solution, many Sunni Arabs have concluded their only realistic option is a violent conflict increasingly framed in confessional terms," according to the group.
A resurgent al Qaeda
In 2008, after an increase in U.S. forces in Iraq and with the aid of Sunni tribes who joined the battle against insurgents, al Qaeda in Iraq appeared to be badly beaten.
But since the 2011 withdrawal of U.S. troops, the Sunni-led group known as the Islamic State of Iraq and the Levant has staged a comeback amid Iraq's growing sectarian tensions -- as well as the conflict in neighboring Syria.
Some, including Republican U.S. Sens. John McCain and Lindsey Graham, have criticized al-Maliki's governing approach for antagonizing Sunnis.
In a letter to Obama ahead of his visit with al-Maliki, the two complained that the prime minister is part of the problem standing between Iraq and greater stability.
"By too often pursuing a sectarian and authoritarian agenda, Prime Minister Maliki and his allies are disenfranchising Sunni Iraqis, marginalizing Kurdish Iraqis, and alienating the many Shia Iraqis who have a democratic, inclusive, and pluralistic vision for their country," they wrote.