US President Donald Trump’s announcement that the US is withdrawing from Syria has left many questions. Eastern Syria is a large and strategic area sandwiched between Turkey and Iraq. Historically it was also a neglected area of Syria. As the US leaves, threats of conflict hang over the millions of residents who wonder what will come next.The area the US is leaving in eastern Syria is neatly separated from the rest of Syria by the Euphrates River. This includes the Syrian governorate of Hasakah, and parts of the governorates of Raqqa and Deir ez-Zor. The only exception is a small area over the Euphrates River where Manbij is located in northern Syria. This is an area of Syria that was deeply affected by the rise of ISIS in 2013. Prior to that, the Kurdish parts of this region had been neglected by the Assad government. Syria stripped 120,000 Kurds of citizenship after 1962. The Assad government has suppressed the Kurdish population with its brand of Arab nationalism, depriving many not only of citizenship, but also pushing them off their lands and seeking to settle Arabs in their place. Kurdish towns were renamed with Arabic names. The suppression created resentment that led to riots in 2004 in Qamishli. In other areas of eastern Syria, particularly along the Euphrates River valley, a different dynamic took place. With some of the country’s only oil fields and government investment in Deir ez-Zor, some areas benefited. But other Arab tribes followed politics in neighboring Iraq, down the river, more than they focused on Damascus. Reports say that some people kept pictures of Saddam Hussein in their houses, not Assad. After the US invasion of Iraq in 2003, instability spread along the border with Iraq as insurgents and foreign fighters used Syria as a corridor to reach Iraq.Baghdad complained to Damascus about the fighters streaming across the border but Syria didn’t stem the flow, either out of a desire to confront the Americans, or hoping that some of the Islamist extremists increasingly making up the rank and file of insurgents would go to Iraq and not bother the Assad regime. Blowback came after the Syrian civil war began, when these networks of extremists, using the Euphrates valley to move back and forth began to attack the Syrian regime. ISIS exploited this instability and rose to power in Raqqa in 2013 because of it.Eastern Syria is a large area, more than twice the size of Israel, almost the size of West Virginia. Resource rich, it has oil in the south near the Euphrates River, and wheat and agriculture in the north along the Turkish border. But it is sparsely populated in many areas, which are desert. Overall the population is several million. It has undergone extreme change during the war with ISIS. Raqqa, liberated in the fall of 2017, still lies in ruin and bodies continue to be discovered from the conflict. OCHA, for instance, identified hundreds of thousands of people in need in eastern Syria in 2018.Drought also struck some areas. A US AID map of the area in 2017 shows that people needed everything from basic nutrition to shelter and clean water. This was true across the Kurdish areas as well as across the areas liberated from ISIS in 2016-2017. In Hasakah province, NGOs from the FAO helped thousands of families by providing seeds to grow cereals.The relative security and stability with which this could be provided was made possible by the Syrian Democratic Forces (SDF) on the ground and their partnership with the US-led Coalition. Together they had defeated ISIS across a huge swath of eastern Syria. Prior to the intervention of the US in 2014, mostly Kurdish areas had been under siege by ISIS which was had conquered a huge area of Syria and Iraq, ruling over millions. Eventually the SDF, which grew out of the Kurdish People’s Protection (YPG) units, became a larger armed force with Arabs, Kurds and other groups. In never shed claims that it was primarily connected to the YPG and thus linked to the Kurdistan Workers Party (PKK). Turkey argued that the YPG was the Syrian version of the PKK, which it and the US view as terrorists.Eastern Syria was one area in the Middle East that didn’t fit into the alliances being formed in the region. One alliance is led by Iran and includes the Syrian government, Hezbollah, Shi’ite militias in Iraq and the Houthis in Lebanon. Another alliance consists of Turkey, Qatar and Syrian opposition factions. A third alliance consists of Saudi Arabia, the UAE, Bahrain and Egypt. Not every country in the Middle East is closely affiliated with these three sides. But most of the Arab countries, such as Jordan, Oman, Kuwait, the Palestinian Authority and others are more closely connected to Riyadh than Doha or Ankara.AS THE US role in eastern Syria grew in 2017 and 2018, some in the Trump administration saw it as a leverage against Iran’s role in Syria. Officials indicated the US would stay for several years to rebuild and stabilize the area so ISIS wouldn’t return and so Iran wouldn’t extend its influence into the area. But Trump saw US involvement in eastern Syria through the lens of US involvement in the Syrian conflict going back to 2011. He said in his speech in Iraq on December 25 that the US was supposed to be in Syria for three months but had stayed for almost 8 years. It was widely thought the US would be in eastern Syria until at least 2021 when the US decided to leave on December 19.This has left a whole area of eastern Syria seemingly “up for grabs” by the powerful states in the region. The phenomenon of eastern Syria being run by the SDF had grown out of the instability of the Arab spring. It was one of those ungoverned spaces, like areas in Yemen and Libya. The Syrian regime had melted away and the YPG had been able to seize parts of Hasakah in 2012 and 2013. It embarked on a unique political experiment, applying its far-left governing principles to eastern Syria, which opponents deride as a form of Marxism. Some of this had been accomplished through quiet discussions with the Syrian regime and even Iran. Turkey, the Kurdish region of northern Iraq, the US, Russia, and even Saudi Arabia all sought to play a role in the eastern Syria region. Each saw different things to gain. This is because the area has become a strategic hinge between Turkey, Iran and areas in Iraq. The extremism that grew out of the Euphrates valley that fed ISIS threatened Syria and Iraq, and became a destination for 50,000 foreign fighters. That makes it a strategic asset for the whole region.The Kurdish success in eastern Syria is also seen as a threat. Turkey views the area as a center of PKK activity which matters to Ankara because since 2015 Turkey has been fighting against a PKK insurgency. Turkey has sought to strike at PKK members in northern Iraq, to reach around behind eastern Syria and cordon off the area. Turkey also intervened in northern Syria and Afrin in northwestern Syria to prevent the YPG from expanding. Turkey now wants to intervene in eastern Syria as a final part of its campaign against the PKK. The US prevented this with its presence.For Russia, eastern Syria is important because it is one more area that it can help the Syrian regime return to Damascus control and a place it can play a role as a mediator, which increases Moscow’s prestige in the region. Russia helped mediate between Iran and Turkey at Astana, Sochi, Geneva and Idlib. In each place, Russia grew in influence as the one country everyone can go to, replacing the role the US used to play in the region. Eastern Syria would be another feather in Moscow’s cap.For Iran, eastern Syria may also be important. It has militias that it backs along the Euphrates river. It would like to have influence and also to prevent an ISIS-resurgence. Already Humam al-Hamoudi, a member of the Islamic Supreme Council of Iraq has claimed the US withdrawal will fuel ISIS resurgence. He didn’t say this to encourage the US to stay, but rather to encourage Iraq and Iran to play a greater role. Press TV in Iran highlighted this. Soon Iran’s media will be pushing for more involvement, via Iraq, part of its desire to carve out a corridor of influence across Syria.The US appears to be walking away, but there are voices in the US who want to continue to wield US influence in eastern Syria. In addition US allies such as the UAE, Saudi Arabia and the Kurdish region in northern Iraq will want to play a role. The Gulf countries are re-establishing relations with Damascus, which might lead them to play a financial role in rebuilding eastern Syria. It’s clear that media in the UAE and Saudi Arabia are concerned about what might happen as Turkey, Russia and Iran angle for control.For Syria the end game is clear. It wants eastern Syria back. Initially in some kind of agreement with the SDF or YPG, it will seek to slowly gobble up the area after being surprised by the speed with which the US appears to be leaving. This doesn’t mean the SDF or other entities, such as the YPG, connected to it are finished. The area is of great importance and these groups have had almost half a decade to put down roots openly, after years of living in the shadows under the Assad regime. It also doesn’t mean the extremist networks of ISIS or the networks of the Syrian rebels are finished. ISIS still holds territory and many of these areas have lived free of the regime for almost eight years. None of this will go quietly into the night.