More NYT:

U.S. Cites Planning Gaps in Iraqi Assault on Basra - NYTIMES 3 April.

Ambassador Ryan C. Crocker first learned of the Iraqi plan on Friday, March 21: Prime Minister Nuri Kamal al-Maliki would be heading to Basra with Iraqi troops to bring order to the city.

But the Iraqi operation was not what the United States expected. Instead of methodically building up their combat power and gradually stepping up operations against renegade militias, Mr. Maliki’s forces lunged into the city, attacking before all of the Iraqi reinforcements had even arrived. By the following Tuesday, a major fight was on.

“The sense we had was that this would be a long-term effort: increased pressure gradually squeezing the Special Groups,” Mr. Crocker said in an interview, using the American term for Iranian-backed militias. “That is not what kind of emerged."

...

The operation indicates that the Iraqi military can quickly organize and deploy forces over considerable distances. Two Iraqi C-130s and several Iraqi helicopters were also involved in the operation, an important step for a military that is still struggling to develop an air combat ability.

But interviews with a wide range of American and military officials also suggest that Mr. Maliki overestimated his military’s abilities and underestimated the scale of the resistance. The Iraqi prime minister also displayed an impulsive leadership style that did not give his forces or that of his most powerful allies, the American and British military, time to prepare.

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As the Iraqi military and civilian casualties grew and the Iraqi planning appeared to be little more than an improvisation, the United States mounted an intensive military and political effort to try to turn around the situation, according to accounts by Mr. Crocker and several American military officials in Baghdad and Washington who spoke on condition of anonymity.

Two senior American military officers — a member of the Navy Seals and a Marine major general — were sent to Basra to help coordinate the Iraqi planning, the military officials said. Soldiers from the 82nd Airborne Division were pressed into service as combat advisers while air controllers were positioned to call in airstrikes on behalf of beleaguered Iraqi units. American transport planes joined the Iraqis in ferrying supplies to Iraqi troops ...