New Bin Laden Tape Begs Iraqi Insurgents to Unite

"Don't be arrogant," bin Laden warned. "Your enemies are trying to break up the jihadi groups. I urge you all to work in one united group."

People familiar with bin Laden's voice say the tape appeared to be authentic, although there was no reference to any event that would indicate when it was recorded.

Bin Laden's message comes at a time when U.S. strategy to split Iraqi insurgent groups from al Qaeda units appears to be working.

There is widespread agreement that AQI has suffered major blows over the past three months. Among the indicators cited is a sharp drop in suicide bombings, the group's signature attack, from more than 60 in January to around 30 a month since July. Captures and interrogations of AQI leaders over the summer had what a senior military intelligence official called a "cascade effect," leading to other killings and captures. The flow of foreign fighters through Syria into Iraq has also diminished, although officials are unsure of the reason and are concerned that the broader al-Qaeda network may be diverting new recruits to Afghanistan and elsewhere.

The deployment of more U.S. and Iraqi forces into AQI strongholds in Anbar province and the Baghdad area, as well as the recruitment of Sunni tribal fighters to combat AQI operatives in those locations, has helped to deprive the militants of a secure base of operations, U.S. military officials said. "They are less and less coordinated, more and more fragmented," Lt. Gen. Raymond T. Odierno, the second-ranking U.S. commander in Iraq, said recently. Describing frayed support structures and supply lines, Odierno estimated that the group's capabilities have been "degraded" by 60 to 70 percent since the beginning of the year.