Reuters
Members of the revolutionary guard attend the anniversary ceremony of Iran's Islamic Revolution at the Khomeini shrine in the Behesht Zahra cemetery, south of Tehran, February 1, 2012.
A campaign of air strikes carried out by a US-led coalition hasn't prevented the Islamic State (also known as ISIS, ISIL, and Daesh) from continuing its campaign of violence.
ISIS seized Ramadi, a provincial capital in Iraq, and Palmyra, an ancient city in Syria, in May and the group is now closing in on Aleppo.
The Soufan Group, a strategic security firm, notes that Iran stands to benefit from the failure of the coalition and Iraqi security forces backed by the US.
Shiite-led Iran has been on the front lines of the fight against ISIS, a Sunni terror group, in Iraq. The militias Iran supports are widely considered the most competent fighting force on the ground in Iraq.
The Iraqi security forces, led by the Shiite-dominated government in Baghdad, withered under a massive ISIS assault in Ramadi, the provincial capital of the Anbar province, last month. The same thing happened last summer in the second largest city of Mosul.
The most successful fighters - ISIS militants and Iran-backed militias - have shown the ability to fight on multiple fronts simultaneously.
"Like the Islamic State, Iran has also built an impressive capacity to operate on several fronts at once and display the strength of its logistics," the note states. "Iran has not only provided arms and money to the Iraqi and Syrian governments, it has also supplied military force, and it has done so in a way that is likely to ensure its influence in the region at least for as long as the Islamic State survives."
For this reason, Iran might not want to completely extinguish ISIS in Iraq and Syria, according to former US Army intelligence officer Michael Pregent.
Michael Pregent
Pregent told Business Insider in April that, while Iran wants to preserve its proxies' control over Baghdad and Damascus, Iran has something to gain from allowing ISIS to continue operating in some other areas.
As long as ISIS survives, Iran can claim that their allies in both countries are the only thing preventing a jihadist takeover, which ensures Tehran's hold on Baghdad and Damascus and provides Iran a degree of international support for their allies in both countries.
The administration of US President Barack Obama has already made it clear that he doesn't want to intervene with the civil war in Syria, partly based on Iran's dominance. The US has a training program for moderate rebels in Syria, but those rebels have reportedly been told to target only ISIS, not the regime of dictator Bashar Assad.
In any case, we're likely to see this fight drag on for a while.
"Iran and the Islamic State both approach Iraq and Syria in the same way. In contrast to the coalition, they see it as a single battlefield requiring a single strategy," The Soufan Group states. "Both see the battle as a fight for long-term influence and expansion, not as one of temporary territorial gains and losses. Both have an advantage over the coalition in having a clear set of objectives they aim to achieve and of interests they wish to protect."