The battle for Raqqa and the thwarting of Iranian ambitions

Rubin Center:

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The battle against the territorial holdings of the Islamic State in Iraq and Syria is reaching its final phase. The re-conquest of Mosul is almost done. The assault on Raqqa city, the capital city of the Caliphate is about to begin. It is set to be a hard and bloody fight. But its eventual outcome is not in question. Islamic State as an entity controlling ground will be destroyed. At which point the movement will revert back to its former status as a clandestine terror network. As the eclipse of the Caliphate draws near, the race is opening up to inherit its former domains.

The competitors in this contest are Iran and its various allies and proxies, and forces associated with the west and the Sunni Arab states.

The Iranians and their allies want to penetrate IS territory from west to east – with the Iraqi Shia militias pushing westwards from Tel Afar and Assad regime forces and pro-Assad militias (including Hizballah) probing east.

The regime forces nosing around in al Tanf are in the process of seeking to seize border areas with both Jordan and Iraq. The US is determined to prevent that. The town of Deir al-Zour and the surrounding oil rich areas will form an important part of the prize.

Pro-western forces, meanwhile are pushing north from Jordan and south from the Kurdish-controlled area north of the IS enclave. The forces engaged on this side are the Syrian Democratic Forces, dominated by the Kurdish YPG, and the Maghawir a-Thawra (Commandos of the Revolution, formerly the New Syrian Army) rebels, supported by the US, UK and Jordan, from the south.

The outcome of this contest is of strategic significance, despite the remote and arid nature of much of the territory concerned. The Iranians want to create a contiguous line of territory controlled by themselves and their allies stretching from Iraq into Syria, and thence to the Mediterranean Sea and the border with Israel.

Islamic State has formed a buffer against the achievement of this goal....
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It is worth also noting that the outcome in eastern Syria is not of primary interest to the Russians. Russia wants to preserve the regime in existence and to keep its naval investments in Latakia Province. Neither of these interests is threatened by events further east. Controlling the east is an Iranian and Assad regime goal only.
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There is much more.

This explains in part the attack by the US on Syrian forces that threatened a special ops camp in the area.  Thwarting Iranian ambitions has to be a key goal not only of the US but other parties in the region including Israel and Jordon.  The battle has become more than just destroying the ISIS caliphate.