“We always knew there would be a point where the effectiveness of the government forces would decline to the point where they could not effectively command and control their forces,” said the diplomat, who was granted anonymity to discuss confidential details of the battle inside Tripoli.

“At the same time,” the diplomat said, “the learning curve for the rebels, with training and equipping, was increasing. What we’ve seen in the past two or three weeks is these two curves have crossed.”

Through Saturday, NATO and its allies had flown 7,459 strike missions, or sorties, attacking thousands of targets, from individual rocket launchers to major military headquarters. The cumulative effect not only destroyed Libya’s military infrastructure but also greatly diminished the ability of Colonel Qaddafi’s commanders to control forces, leaving even committed fighting units unable to move, resupply or coordinate operations.

On Saturday, the last day NATO reported its strikes, the alliance flew only 39 sorties against 29 targets, 22 of them in Tripoli. In the weeks after the initial bombardments in March, by contrast, the allies routinely flew 60 or more sorties a day.

“NATO got smarter,” said Frederic Wehrey, a senior policy analyst with the RAND Corporation who follows Libya closely. “The strikes were better controlled. There was better coordination in avoiding collateral damage.” The rebels, while ill-trained and poorly organized even now, made the most of NATO’s direct and indirect support, becoming more effective in selecting targets and transmitting their location, using technology provided by individual NATO allies, to NATO’s targeting team in Italy.