Pbs.org |  by Jason M. Breslow

As the Islamic State continues its march through Syria and Iraq, the jihadist group is quietly utilizing a network of former members of Saddam Hussein’s Baath Party to help militarize a fighting force that has effectively erased the border between both nations and left roughly 6 million people under its rule.

The extent of this seemingly mismatched alliance is detailed in a new report by the New York-based intelligence firm, The Soufan Group. Despite a deep philosophical divide between ISIS and the Baath Party, the two sides have found “sufficient coincidence of interest to overcome any ideological disagreement,” the analysis, which will be released on Wednesday, found.

This “marriage of convenience,” as the report’s author, Richard Barrett describes it, can be seen throughout the ISIS hierarchy. The current head of the group’s military council, for example, is believed to be Abu Ahmad al Alwani, an ex-member of Saddam Hussein’s army. So too was al Alwani’s predecessor. Another member of the military council, Abu Muhanad al Sweidawi, was once a lieutenant colonel in Hussein’s air defense intelligence, but by early 2014 was heading ISIS operations in western Syria, according to the report.

Similarly, two deputies to the Islamic State’s self-proclaimed caliph, Abu Bakr al Baghdadi, are former Baathists: Abu Muslim al Afari al Turkmani is believed to have been a senior special forces officer and a member of military intelligence in Hussein’s army. Today, as Baghdadi’s number two, he supervises ISIS operations in Iraq. The second deputy, Abu Ali al Anbari oversees operations in Syria. Both men are also thought to serve on the Islamic State’s main governing body, known as the Shura Council.

Even the appointment of al Baghdadi to lead the Islamic State of Iraq in 2010 is reported by an ISIS defector to have been engineered by a former Baathist: Haji Bakr, an ex-colonel from the Iraqi Revolutionary Guard. Bakr “initially attracted criticism from fellow members of the group for his lack of a proper beard and lax observance of other dictates of their religious practice,” the report notes, “But his organizational skills, knowledge of the Iraqi Army and network of fellow ex-Baathists made him a valuable resource.”

It’s this type of expertise and network of connections that has made former Baathists so valuable to the Islamic State, says Barrett. Case in point, he says, is the long-term planning and preparation seen in the Islamic State’s capture of Nineveh Province and its capital, Mosul, in June 2014. As he writes of the campaign:

This is not the work of neophyte enthusiasts inspired by their imagined rewards of martyrdom, it is clearly the result of detailed planning by people who know Iraq well, have prior experience and training, and are able to manage an organization with discipline and secrecy; all characteristics of Saddam Hussein’s Baathist supporters.

The incentives for ex-Baathists may be equally opportunistic.

“What the Baathists probably get out of it is a way back into Iraq,” says Brian Fishman, a counterterrorism research fellow at the New America Foundation. Before the Islamic State’s emergence, Fishman notes, many Baathists had been effectively forced out of Iraq to neighboring Syria. Today, they’re back home, slowly acquiring influence and territory.

The question is, how long can the alliance last? One of the few points the two groups agree on, analysts say, is restoring Sunni rule in Iraq. Fundamentally, however, ISIS is focused on expanding the Islamic caliphate that it declared on June 29, 2014. For its part, the Baath Party in Iraq has been a largely secular, nationalist movement.

Some fissures have already begun to surface. In July, for example, Reuters reported that Sunni militants that helped ISIS capture Mosul rounded up as many as 60 senior ex-military officers and other onetime members of the Baath Party. That same month, a rival Sunni group made up of many former Baathists issued a statement denouncing the Islamic State’s persecution of Iraq’s religious minorities.

But predicting just how deep any split may go is hard to tell. On the one hand, says Barrett, ex-Baathists may decide it’s in their interest to continue harnessing the energy of ISIS in order to regain prominence in Iraq. Barrett says its easy to see ex-Baathists then tell themselves, “Once we achieve our objectives, our political objectives, then we’ll sort out all this business about these crazies who believe in a caliphate.”

On the other hand, Baathists may simply come to the conclusion that there is nowhere else for them to go. “They’re going to make the best of a bad job in a way,” Barrett says.

Fishman sees a similar decision facing former Baathists, but he warns against assuming the block will act in concert. It’s important to remember, he notes, that beginning in late 2006, Baathists faced a comparable scenario, and while some opted to continue their involvement in the Iraqi insurgency, others chose to align themselves with the U.S. against Sunni militants.

For the Islamists, meanwhile, their view of the alliance may end up being guided more by politics than it is by ideology, says Fishman.

“ISIS at the end of the day is a political actor, and they have this sort of extreme, even ideological perspective, but that is all framed through who is helping us on the battlefield and who’s not,” he says. “If you’re helping them on the battlefield, they’re going to find a reason to think you’re a good guy. If you are not helping them on the battlefield, they’re going to find a reason to think you’re a bad guy.”