ISIS leaders are fleeing to Syrian city of Deir el-Zour in Middle Euphrates River Valley

Washington Times:

For all the focus on the battle to capture Raqqa, the climactic battle against the Islamic State in Syria may be about to take place along a relatively unknown river valley miles away from the group’s self-styled “caliphate” capital.

Military commanders in Damascus, Tehran and Moscow are setting their sights on the Syrian city of Deir el-Zour and the surrounding Middle Euphrates River Valley as the battleground for the fight against the jihadi group, also known as ISIS or ISIL.

Located 90 miles from Raqqa, where U.S.-backed militias began their assault to retake the city last week, the fertile stretch of land along the banks of the Euphrates River is home to Madan, Deir el-Zour and other Islamic State redoubts. Many of the group’s leaders, including “caliph” Abu Bakr al-Baghdadi, have fled to the area.


Coalition commanders and Pentagon officials say the overall battle plan will address the Islamic State buildup in Deir el-Zour. But with all eyes fixed on Raqqa, it remains to be seen how Syrian-led operations, backed by Russia, will affect that long-term strategy.

Elements of the U.S.-backed Syrian Democratic Forces, or SDF, have borne the brunt of the fighting in and around Deir el-Zour. But the Raqqa operation is drawing focus away from the Middle Euphrates River Valley, leaving Syrian government forces and paramilitary groups backing the regime of President Bashar Assad to defend the area against Islamic State militants.

Damascus and minders in Moscow are having difficulty reining in Iranian Shiite paramilitaries tied to the regime. The Iranian troops are playing their own regional game in southern Syria, antagonizing U.S. forces who trained local fighters to carry out coalition operations against the Islamic State in the Middle Euphrates River Valley.
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Islamic State leaders, including al-Baghdadi, reportedly began fleeing Raqqa for Deir el-Zour, Madan and other areas in the Middle Euphrates River Valley en masse in May, officials at U.S. Central Command said at the time.

Their escape, likely prompted by the coalition’s advances in Mosul, convinced factions within the group’s leadership “from a military perspective, that this may not be tenable to hold on to Raqqa,” said a command official speaking on the condition of anonymity.

U.S. military planners, including top coalition commander Lt. Gen. Stephen Townsend, sought to expedite the Raqqa offensive in part to ensure top leaders of the Islamic State were not able to escape the coalition’s tightening noose around the city.

But outside factors, including ongoing tensions between the U.S. and Turkey over the Kurdish role in the operation, ultimately hindered efforts to speed up the Raqqa assault. A week into the operation to liberate Raqqa, questions over the true strategic importance of the city have only grown louder within defense and national security circles.
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There is much more.

Syria remains a battle space of many factions.  Iran, Russia, and the Syrian government will continue to try to claim the ground liberated from ISIS by US backed forces.  This is likely to lead to direct contact with Americans supporting the forces fighting ISIS.