Team Sunni

The big name on the Sunni side is ISIS. The insurgent group originally started in the mid-2000s during the Iraq War, where the group developed a lot of close relationships and affiliated closely with local al Qaeda franchises. But ISIS really hit its stride in the Syrian Civil War, gaining some notoriety as the folks who were so psycho that they got dumped by al Qaeda. It’s not entirely clear whether psychopathy was actually the reason for the split, or whether it was an administrative and bureaucratic turf fight that got of hand, but you’re likely to hear both claims in the coming days.

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Team Shia

Maliki has been beating on the Sunni and the Kurds in much the same way that Saddam was beating on the Shia and the Kurds, except for two things. One, Maliki hasn’t been putting a non-sectarian, nationalist political frosting over the top of it. Two, Saddam was only broadly known and understood to be a proxy for the Saudis and Gulf Arab States; Maliki and has been a lot more open about getting in bed with his benefactors, the Iranians, relying on them for things like delivering key voting blocks to maintain his grip on power.

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Team Kurd

One potential winner in all of this might be the Kurds, an ethnic minority in northern Iraq, northwestern Iran, northeastern Syria, and easternmost Turkey. Without their own state, they’ve been under the heel of the central government in just about every country they’re found in. However, one of the consequences of turmoil in Iraq in recent decades has been the establishment of a fairly autonomous Kurdish regional government in northern Iraq. Then, during the ongoing Syrian conflict, Syrian Kurds have also taken the opportunity to carve out their own chunk of territory, effectively managing a Syrian Kurdistan which has been able to protect its borders and largely avoid being drawn into the main fighting.

https://news.vice.com/article/heres-who-is-fighting-in-iraq-and-why