Looks like Bush is right for a change.... just not in the way he thought.
This article by Gareth Porter does a nice job of pointing out how, when the Basra offensive started looking like a failure, both Bush Administration and US Military representatives started blaming Maliki for the conflict. It also makes it clear that instead of blaming Iraqi Prime Minister Maliki for the failure in Basra, we should probably put the blame where it belongs... on General Petraeus.
Apparently, Petraeus is good at bargaining with Iraqis, good at buying and negotiating peace in counterinsurgencies, good at counterterrorism... but not all that hot at training and appointing Iraqi commanders, coordinating major military operations with the presumption of possible local uprisings, and at getting actionable intelligence from within the Sadrist community.
The operation was a major intelligence failure, where, despite detaining approximately 2000 Sadrists in the run-up to the attack on Basra, General Petraeus apparently had no clue as to the strength of Sadr's forces, the level of support to expect from the Shi'ite community, and the threat that Sadrists would pose throughout Baghdad and other cities. Likewise, he clearly overestimated the ability of Iraqi security forces to wage this fight on their own.
Petraeus apparently thought that Sadr backed down repeatedly over the last few months due to military weakness and due to Iranian influence in Sadr's decision-making, rather than as a tactic to both wait out his enemy and to gather and conserve his strength. Iraqi forces weren't up to the task of attacking the Sadrists, and, in many cases, they melted, with both Iraqi troops and Iraqi leaders retreating, refusing to fight, or outright surrendering their arms when faced with Sadrist opposition.
To make matters worse, when Petraeus decided to send in his own forces, he did so in a piecemeal, indecisive fashion, rope-a-doped into attacking a strong enemy who, ironically, grows all the stronger when he doesn't have to fight protracted conflicts. Given that the very act of sending in US troops came with a real cost -- the undermining of the whole premise of the operation, and the strengthening of the moral argument for the Sadrists -- the fact that Gen. Petraeus did not execute decisively when he chose to cross that line compounded the nature of the defeat.
The Sadrists now appear strong, both militarily and morally. If they can maintain this appearance of strength, this appearance of being able to bring security, to resist occupation, resist Maliki, and resist rival factions, then it's hard not to imagine that they'll be the dominant party in the next elections, which could bring about a firm, rapid timetable for US withdrawl.
Unless Sadr can be either provoked to violence or taken down in a clearly antidemocratic putsch, it's hard to imagine that Iraqis won't democratically rid themselves of occupation. And given that this conflict was probably the last great chance of the US and the current Iraqi government to resist these ends, the Sadrist's victory in Basra will, indeed, likely be a defining moment in the history of a free Iraq.