Clashes between Iraqi forces and Shiite militiamen widened Thursday in Basra, Iraq's second-biggest city, and reverberated in Baghdad, where tens of thousands protested the Iraqi army's assault.
The stakes are high for U.S.-backed Prime Minister Nouri al-Maliki, who vowed Thursday to fight "until the end" in Basra.
Why is the Iraqi government fighting in Basra?
Maliki dispatched Iraqi forces to Basra to uproot the Mahdi Army from the important oil center. The Mahdi Army, led by anti-American cleric Muqtada al-Sadr, has grown increasingly restive in recent months because it says the Americans and their Iraqi allies have been arresting hundreds of Sadr's followers.
Basra, which Maliki calls "Iraq's lung," has come under the sway of the Mahdi Army and other militias, which are fighting one another for control of the vital port city and its oil assets.
Didn't Iraqi security forces have control over Basra?
That was the explanation when the British withdrew their forces in December. But since then evidence has emerged that the police in Basra have been infiltrated by Mahdi Army militia.
Aren't Maliki and Sadr both Shiites?
Yes, but Maliki's Dawa party draws support from the Supreme Islamic Iraqi Council, which is the main Shiite rival of Sadr. In addition, the Iraqi security forces are dominated by the Badr Brigade, rivals of the Sadrists.
Does this have anything to do with elections later this year?
That is what Sadr's supporters say is Maliki's motivation. According to them, the prime minister wants to weaken support for Sadr before the provincial elections, which are expected in the fall.
What is at stake in Basra?
Quite a lot. The crackdown is a big gamble for Maliki. Failure could weaken his fragile coalition of support at a time he is trying to unite Shiites, Kurds and Sunnis to pass important laws on oil revenue sharing. In the short term, the crackdown could collapse a cease-fire ordered by Sadr in August. Sadr's cease-fire, along with the increase in U.S. troops and the rise of Sunni chieftains against Islamist extremists, has been credited for lowering violence throughout the country.
Longer term, a failure to dislodge the militias in Basra could sow instability in other areas of the country, undermining the authority of the Iraqi government and delaying the withdrawal of U.S. troops.
"The fight is another potential turning point," said John McCreary, a former Defense Intelligence Agency analyst. "If Maliki does not win in Basra, he will not win anywhere, and instability will increase. If he stabilizes Basra, he gets the chance to repeat his success in another town."
Some worry that this is the beginning of a Shi'a civil war.
What has the United States said about the operation?
President Bush praised the "great courage" of Iraqi officials to confront the militias.
The operation is "an indication of the continued maturation of this government in its willingness and capacity to take increasing responsibility for security," said national security adviser Stephen Hadley.
How is the battle going?
Maliki, who traveled to Basra to supervise the operation, has vowed "no retreat." But the fighting has been more intense than some Iraqi officials anticipated. Special police units sent from Baghdad have been beset by dissent after they were fired upon by police loyal to Sadr. Soldiers have deserted, with an unspecified number taking off their uniforms and walking away. Some soldiers complained they were outgunned by militiamen who are using sniper fire, mortars and rocket-propelled grenades.
U.S. forces are not involved in the operation.
The street battles that started Tuesday in Basra and in Baghdad's Sadr City have spread to other neighborhoods and cities and left more than 200 dead.
How are the civilians in Basra faring?
Shortages of food, water and other basic necessities have been reported.
Will Sadr surrender?
Today is the deadline imposed by Maliki, who has promised harsher measures will ensue otherwise. On Thursday, Sadr called for a "political solution" to the standoff, but he has given no other indication that he or the other militias would lay down their weapons.
Information from the Associated Press, Washington Post and Guardian of London was used in this report.
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