Are Iraq and Syria's campaigns against Islamic State about to converge?

Islamic State's (ISIS) infamous takeover of one-third of Iraq in 2014 was in many respects a large form of spillover from the conflict in neighbouring Syria. Today, as both countries are reconquering the remnants of Iraqi and Syrian territory the militants control their separate campaigns may well conjoin to finish the militants. 


General Saleem Harba, a man Russia's state-run Sputnik news cited as a Syrian military expert, said as much. He anticipates that the Syrian military's campaign in Deir ez-Zor will need to be coordinated with the Iraqi Army, especially in the Syrian border regions of al-Mayadeen and Al Bukamal (close to the Iraqi border town of Al Qaim) where the militants are expected to make their last stand. 

“The Syrian army will also have to coordinate its actions with the Iraqi armed forces,” Harba insisted. “Only this way is it possible to completely destroy the remnants of the terrorist forces.”
 
Harba is certainly correct to a large extent. Both sides need to simultaneously finish ISIS off near the porous border to prevent them from using either side as a sanctuary to recover from military defeats. A pincer movement in Deir ez-Zor and the western part of Iraq's Anbar province (where the militants still have some small pockets of territory) will deny them any foothold and is a sure way to uproot them from their remaining holdouts. 

ISIS first attained territory in January 2014, in both Raqqa and the Iraqi city of Fallujah. This was due to the weakness of the Syrian regime in western Syria and the instability in Fallujah, a direct result of the 2013 Iraqi Sunni protests against then Prime Minister Nouri al-Maliki, who moved to subdue them with military force. 

The militants later symbolically erased the Iraqi-Syrian frontier during the fall of Mosul in June 2014. Their looming defeat may well see Baghdad and Damascus completely reinstate and reinforce that border. However, even before the bloody rise of ISIS that border has been extremely porous. As early as March 2013, for example, some Syrian Army soldiers briefly crossed the border into Iraq amid clashes only to be attacked by militants believed to be Al-Qaeda in Iraq, ISIS's predecessor. At least 42 of them were subsequently killed alongside nine Iraqi soldiers. 

Aside from the ISIS's disdain for that border there has been some brief overlap between Iraq and Syria targeting militants on each other’s territory. The earliest was in June 2014 when Syrian jet fighter-bombers targeted ISIS just over the border in the aforementioned Anbar town of Al Qaim. Prime Minister Maliki hailed the attack but claimed that “We didn't make any request from Syria. They carry out their strikes and we carry out ours. The final winners are our two countries” since “this group targets both Iraq and Syria.” 

More recently, last February, Iraqi F-16s launched cross-border airstrikes against ISIS in Deir ez-Zor in an operation Baghdad said it coordinated with Damascus. Future Iraqi airstrikes in Deir ez-Zor can be coordinated with Damascus, alongside offensives in Anbar itself to ensure Syrian success in Deir is bolstered by a simultaneous ISIS defeat across the border. 

Coordination between Iraq and Syria, along with Russia's military forces in Syria, will not prove very difficult since they have already established the Russian-Iranian-Iraqi-Syrian coalition (which has two command centers, one in Damascus and the other in Baghdad's Green Zone) in September 2015 to coordinate actions against the militants. Unlike its backer, the US-led anti-ISIS coalition, Baghdad has no qualms about militarily coordinating actions against ISIS with the Russians and/or the Syrian regime. 

There is some distrust however. Iraqi and Kurdish officials were outraged by the deal Hezbollah reached with ISIS late last month, in which they permitted the militants to leave the Lebanese border on air-conditioned buses to the Iraqi border. 

The very nature of the deal stunk in the eyes of many Iraqis, with Prime Minister Haider al-Abadi declaring it “unacceptable” and an “insult to the Iraqi people.” 

Furthermore, leading Shiite authorities in Iraq, namely Muqtada al-Sadr and Ayatollah Ali al-Sistani, are not supportive of Iran's actions in Iraq or the region. They've never endorsed Iraqi Shiite volunteers who travel to Syria to fight on behalf of the Assad regime, a key strategic ally of Tehran, nor the continued existence of a parallel fighting force to the Iraqi Army, the Hashd al-Shaabi. 

Nevertheless, Baghdad sees eye-to-eye with Damascus on the need to deal ISIS a mortal defeat in both countries. This is sufficient enough to encourage close military coordination between ISIS to surround and crush the remainder of the caliphate from all sides.