At first sight, the war in Iraq shows clear signs of expanding in the coming weeks. ISIL and other Sunni rebels are now in control of most of northwest Iraq as well as the western province of Anbar, raising the prospect of a stable territory across northern Syria and Iraq where a radical Islamist caliphate can be established. The forces of Iraq's Shi'a prime minister Nouri al-Maliki are stretched, though substantial Shi’a militias are rapidly reforming to counter ISIL.

In addition, United States weaponry and contingents are being increased in the Gulf, while nearly half of the US's promised 300 special forces have already arrived in Baghdad. For its part, Iran has deployed its own experienced special-forces officers in Iraq; and in a development neglected by most western media, Syrian strike-aircraft have crossed the Iraqi border in support of Maliki's government, bombing rebel forces in western Anbar province. Around fifty people were killed (see "Syrian Warplanes Strike in Western Iraq, Killing at Least 50 People", Wall Street Journal, 25 June 2014).

Amid this kaleidoscope, the image of ISIL currently being projected - of a united, effective and focused insurgency under cohesive radical Islamist leadership - is misleading. But to determine the movement's actual role requires an overall assessment of recent developments and the various forces involved.

The rebel strategy

What, then, of the rebel advances and their aims? Two initial major targets were Iraq’s largest oil-refinery at Baiji and the air-base at Balad (see "ISIL, Iraq, and intervention", 16 June 2014)  A further focus has been the Haditha hydro-electric plant on the Euphrates, the scene of much fighting in recent days.

The Baiji refinery supplies more than half of Iraq’s domestic needs and the town is also the site of a large gas-fired power-station that feeds electricity to Baghdad and other parts of central Iraq. The German engineering company Siemens signed a four-year contract in February 2014 to maintain and upgrade the 600-MW power-plant, but its staff has now been evacuated from the site.

Balad air-base to the south was an integral part of one of the largest concentrations of US troops, Camp Anaconda, during the occupation. It has been in transition to an Iraqi base and was scheduled to receive a consignment of F-16 strike-aircraft that the US was in the process of supplying to the Iraqi government. Perhaps as many as a thousand US personnel, including contractors, private-security staff and military trainers were at the base until mid-June 2014 but were reportedly withdrawn very soon after the rebellion started.

The rebels aim to take this base for three main reasons: to demonstrate their capabilities, to procure the equipment and arms located there, and to prevent any government using it to challenge's ISIL's construction of its planned caliphate in the region. The last is a feature of the recent paramilitary advances, which indicate considerable logistical abilities by ISIL and its associates. Indeed, Humvees and other US equipment looted from Iraqi army bases in Mosul have already been used in ISIL attacks over the border in Syria.

On the electricity-supply side, Iraq suffers from chronic shortages of power, with very few parts of the country having a reliable round-the-clock supply. If the rebels gain and then keep control of the Baiji plant and the Haditha dam, with its 660 MW turbines, this will add to the even larger power-plant at the Mosul dam which is in an area they now effectively control. These, together with other gas-fired stations will give them major power-capacity while preventing supplies being delivered to other parts of Iraq. The Haditha dam is also important in the irrigation of crops further down the Euphrates in Shi’a regions of Iraq.

If all these elements are combined, it means that the rebels under ISIL have considerable potential for long-term consolidation within Iraq, in addition to their territorial control in northern Syria (see "Iraq, and the 9/11 echo", 12 June 2014). This is a situation unacceptable to many western governments, not least the United States which is supplementing its considerable military forces in the region. Even without reinforcements, the Pentagon has numerous air-force units available, especially in Qatar, with additional basing facilities in Kuwait and Oman, as well as the US navy’s fifth-fleet HQ in Bahrain.

As to air power, there are currently 90-100 aircraft available, mostly F-15E, F-16 and F-22 strike-aircraft, A-10 ground-attack aircraft, B-1B strategic bombers, C-130 and C-17 transport aircraft, KC-135 tankers and a range of drones (see Grace Jean, “USAF ‘ready within hours’ for airstrikes in Iraq”, Jane’s Defence Weekly, 25 June 2014). All these forces could be expanded in a matter of days and, in addition, a carrier battle-group based on the Nimitz-class carrier, the USS George HW Bush, has been moved into the Gulf with its air wing of around eighty aircraft (see Grace Jean, “US warships positioned in the Gulf”, Jane’s Defence Weekly, 25 June 2014).

F-18 aircraft from the carrier are already involved in surveillance flights across Iraq with intelligence data being supplemented by drone and satellite reconnaissance. Other ships in the group include two missile-ships, the cruiser USS Philippine Sea and the destroyer USS Truxtun, together equipped with up to a hundred cruise-missiles. A destroyer, the USS Arleigh Burke, and a large amphibious warfare ship with 550 marines on board, the USS Mesa Verde, are also in the Gulf. 

The overall picture, therefore is that ISIL and other Sunni rebel forces have taken over substantial parts of northwestern Iraq and are clearly aiming for strategic gains in the form of refineries, power-plants and dams. They appear strong and effective and while they may not be able to move much further, given the rise of the powerful Shi’a militias, they will prove almost impossible for the Iraqi government to defeat. Direct outside assistance will be required and the United States has the forces readily available. On the face of it, an escalating confrontation is all too plausible.

The geopolitical context

But three other factors complicate this situation.

First, Barack Obama's administration is deeply reluctant to get involved in direct conflict, even if this were limited to selective use of airpower in its many forms - from armed-drones through to strategic bombers. Apart from the risk of civilian casualties and the inherent difficulties in acting against entrenched paramilitaries in urban environments, any such moves would mean the US acting in direct military concert not just with Iran but with Bashar al-Assad’s Syria as well.

Second, Obama has advisers alert enough to understand that ISIL planners would dearly love direct US intervention. Indeed the only thing they would like more would be Israeli involvement - a “crusader-Zionist" attack would be an utter gift to their skilled propagandists.

Third, the territory and forces now on the ISIL side present new and far from straightforward challenges. ISIL should be seen not as an integrated force but as a catalyst for a disparate insurgency that is rooted as much in bitter opposition to Maliki’s rule coming from old-time Ba’athists and many local clans, people who may be very far from espousing ISIL's Islamist vision. 

There has already been confrontation between ISIL and the main Ba’athist group (JRTN), including fighting near Mosul. This also reflects differences of strategy: it is likely that ISIL wants to consolidate its power and plan for the longer term rather than overstretch itself across more of Iraq (see “ISIS at Jordan border, but West taking military action would only help rebels”, The Conversation, 23 June 2014).

The implication of this analysis is that a period of stalemate in the conflict may be more likely than an escalation. There is, though, an element of regional geopolitics which has to be factored in. Iran is determined to find the means to contain ISIL in Iraq, limiting its influence to an absolute minimum; at the same time, powerful groups and individuals in western Gulf states such as Kuwait, Qatar and (especially) Saudi Arabia are still backing ISIL to the hilt and will continue to ensure it is well-funded.

Whatever denials may come from the House of Saud, this is the reality, born out of the long-standing rivalry between Saudi Arabia and Iran. It has been said before that any hope of an end to the disastrous war in Syria requires cooperation between Riyadh and Tehran. That now applies just as much to Iraq.