The impact of the withdrawal of the American troops from Syria on the campaign against ISIS (Initial Assessment)


On December 19, 2018, four years after the American campaign against ISIS began, President Trump announced that ISIS had been defeated and America had won. Therefore, Trump and the American administration announced that the United States would withdraw its troops from Syria over a period of several months. According to “senior Americans” quoted by Reuters, America’s aerial strikes against ISIS would also come to an end (according to another source quoted by the Washington Post, the matter of aerial strikes is still under consideration).

  • An ITIC analysis of ISIS’s current situation reveals that the organization was not defeated, although it was weakened after the collapse of the Islamic Caliphate. ISIS continues intensive terrorist and guerrilla attacks in its core countries (Syria and Iraq) despite the strong pressure exerted on it. ISIS attacks also continue in its provinces around the globe (where activities have intensified since the collapse of the Islamic Caliphate). ISIS’s survival in the post-Caliphate era is additional proof of its ability to change its methods and adapt to changing situations. During 2018 ISIS turned itself into a terrorist-guerrilla organization centered in Syria and Iraq, whose operations are decentralized and which does not have to defend a territory or be responsible for the lives of a large population (third generation ISIS[1]).
  • In the meantime, America and the coalition countries continue their intensive aerial strikes against ISIS, focusing on the Euphrates Valley. From a military perspective, the end of American activity in Syria is liable to be detrimental to the campaign currently being waged by the Kurdish forces east of the Euphrates against last important ISIS-controlled area in Syria. The blow is expected to be particularly hard if America stops its aerial support to the Syrian Democratic Forces (SDF). However, in ITIC assessment, the most serious impact of the American pullout is expected to be its influence on morale and the political situation: the Kurds, who control extensive areas in the northeastern part of the country, feel betrayed and their cohesiveness may be harmed. Thus they can be expected to look for new strategic support, especially from the Syrian regime and Russia. The Kurds’ motivation to continue fighting ISIS may be reduced and they may retreat to the heart of their area of control in northeastern Syria and stop clearing the lower Euphrates Valley of ISIS fighters (the first indications were the statements from Kurdish spokesman after Trump’s announcement).
  • The American pullout from Syria (and its possible pullout from Afghanistan) may be regarded by the jihadists, the local Syrian population and even the international community as an American flight and an ISIS victory (and possibly an al-Qaeda victory). That may raise ISIS’s motivation in its various provinces beyond Syria and Iraq and increase the fighting (especially in Afghanistan and West Africa). It is also possible that ISIS operatives and supporters abroad, in addition to supporters of al-Qaeda and other jihadist organizations, will strive to increase the number and seriousness of ISIS-inspired attacks in Western countries. Their propaganda machine will send public messages that despite the loss of the territorial Caliphate, the Americans were defeated and in the final analysis, fled from Syria in disgrace.
Trump announces the pullout of American troops from Syria
  • On December 19, 2018, Trump tweeted that the United States had defeated ISIS in Syria. He also tweeted that “We won.” Therefore, according to Trump, there is no reason for American military personnel to remain in Syria. Spokesmen for the American Departments of State and Defense reported that the United States had begun pulling troops out of Syria, but said that America would continue working with its partners everywhere ISIS operated (Reuters, December 19, 2018). On the other hand, the Americans announced their military personnel would remain in Iraq.

(Trump's Twitter account, December 19, 2018).

(Trump’s Twitter account, December 19, 2018).

Four years before Trump: Obama on beginning the campaign against ISIS[2] (White House website, September 10, 2014).

Four years before Trump: Obama on beginning the campaign against ISIS[2]
(White House website, September 10, 2014).

  • “Senior Americans” said the pullout of the 2,000 American soldiers in Syria would take between sixty and a hundred days. The pullout will be implemented slowly and coordinated [with America’s allies]. Senior Americans and Turks claimed Trump’s decision was based on a phone conversation between the White House and Erdogan on December 14, 2018, during which Erdogan assured Trump ISIS had been nearly defeated in Syria and that Turkey would continue to fight. Trump reportedly said, “Syria is all yours. We’re done” (, December 24, 2018). Trump’s decision was widely criticized in the United States and led to the resignation of Secretary of Defense James Mattis and Brett McGurk, the special envoy to the anti-ISIS coalition.
  • “Senior Americans” reported that America’s aerial campaign against ISIS would also end (Reuters, December 20, 2018). However, according to a different report, a senior Pentagon figure said the administration had not yet decided whether American will continue its aerial strikes against ISIS once the troops pull out of Syria (Washington Post, December 21, 2018). The issue of the aerial strikes may have significant influence on the Kurds’ military campaign and on the message the United States sends to all the actors inside and outside Syria.
Initial assessment of the impact of the American pullout[3]


In the ground campaign against ISIS in Syria during 2018 the Americans played a secondary role. Most of the fighting was conducted by the Syrian army and the forces supporting it, with Russian air support. They took over the regions ISIS had occupied in the southern part of Damascus (the Yarmouk refugee camp), the southern Golan Heights and the region northeast of Suwayda. In ITIC assessment America’s main contribution was its aerial support (as part of the coalition) to the Kurdish forces (SDF) fighting ISIS on the eastern bank of the Euphrates River. In addition to aerial support there were about 2,000 advisers, who improved the Kurds’ military capabilities. The presence of the American advisers increased American political support, which aided the Kurds in defending their home front against Turkish expansionist aspirations, allowing the Kurds to launch their campaign against ISIS. From a military perspective, the main blow to the SDF will be the end of aerial support. It will also be a blow to the Kurds’ morale and political situation, as they will feel exposed to power plays by Turkey, which can be expected to increase its force in northern and eastern Syria.

Significance of stopping American support for the Kurds
  • American (and international) support for the Kurdish campaign in Syria against ISIS has been given in various ways:
    • Intensive aerial support is given to the Kurdish forces fighting ISIS, which has been, in ITIC assessment, the most important form of support. The systematic attacks carried out by the coalition planes damaged ISIS infrastructures and targets and made it difficult for the organization to defend itself and launch counterattacks. The aerial support improved the SDF ground forces’ defensive and offensive capabilities, especially in urban warfare in places like Hajin (ISIS’s stronghold) or in exposed desert regions. If aerial support is in fact stopped, the Kurdish forces will most likely lose their clear advantage in the war on ISIS. ISIS, on the other hand, will be able to use its forces with more flexibility in urban and desert settings and cross the border between Syria and Iraq more easily.
    • The support on the ground, exemplified by the 2,000 American soldiers in regions controlled by the SDF. The number of American personnel is not large, relative to the tens of thousands of Kurdish fighters involved in the anti-ISIS campaign (several thousand of whom are in the lower Euphrates Valley), and relative to the Syrian army and the forces supporting it fighting ISIS in other arenas. Most of the American military personnel do not have combat roles but rather serve in advisory positions to the Kurds. They provide the SDF with artillery support, mark targets for aerial attack, and deal with gathering intelligence and “special operations.” In ITIC assessment, withdrawing the American military personnel will not significantly harm the Kurdish military force (which has shown a high level of military capability as a fighting force), at least not in the short term.
    • Political support. In ITIC assessment, the presence of American troops in the area controlled by the Kurds has great political importance, especially to the west of the Euphrates (the area around Manbij): the presence of American troops and the American flag has so far deterred Turkey from operating against the Kurds, even to the west of the Euphrates. In ITIC assessment, the feeling of betrayal and lack of political support is the most important negative consequence of Trump’s announcement. It is liable to result in the Kurds’ stopping their campaign against ISIS in the lower Euphrates Valley and turning their attention to the north, their border with Turkey (the first indications can be found in statements by Kurdish spokesman after the announcement).
  • So far there has not yet been a decrease in the level of SDF fighting in the ISIS enclave. However, the timing of Trump’s announcement was particularly problematic for the SDF forces. After more than three months of fighting, on the eve of the announcement the SDF occupied most of the city of Hajin (an ISIS stronghold east of the Euphrates). The SDF forces suffered a blow to their morale, and now face ISIS counterattacks which grew stronger after Trump’s announcement. It is still unclear how the fighting will develop, but apparently the SDF’s momentum in fighting ISIS’s enclave north of Albukamal will wane, especially in a scenario where the Kurdish forces’ attention turns towards the border with Turkey, which is considered the Kurds’ main enemy.

ISIS ATVs and motorcycles move through an open area during an attack on SDF forces (ISIS's al-Sham-al-Barakah province, December 21, 2018).
ISIS ATVs and motorcycles move through an open area during an attack on SDF forces (ISIS’s al-Sham-al-Barakah province, December 21, 2018).

  • The exit of the SDF forces from the lower Euphrates Valley, where Syria’s large oil fields lie, is liable to create a security vacuum that will probably be filled by Syrian army forces (with Russian support) and forces operated by Iran (the Iraqi Shi’ite militias and Hezbollah).In the short term, the fighting against ISIS in the Euphrates Valley may continue in the current format, but in the medium and long terms, the Kurds may be more limited in trying to increase their control over territories and will return to the heart of their own territory. In such a scenario, the SDF will cease to be a dominant actor in the Euphrates Valley and the importance of the Syrian regime (with Russian support) will increase, as will the importance of the Shi’ite militias operated by Iran. They will try to fill the resulting vacuum to promote their own security, economic (oil fields) and political interests. Some of those interests have significance for Israel, for example increasing the overland route from Iran to Syria that runs through Albukamal (and through al-Tanf, the shortest overland route). In addition, in ITIC assessment, at this stage ISIS will try to reestablish itself in the enclave north of Albukamal and continue to increase the area under its control to the east and west.

Map of the areas of control in Syria (as of December 20, 2018): under Syrian regime control (red); under Kurdish control (yellow); controlled by the rebel organizations in the Tanf enclave (green); controlled by coalition forces (blue); controlled by ISIS (black and lined); uncontrolled by an organization or country (white) (Nours Syrian Institute for Strategic Studies, December 20, 2018).
Map of the areas of control in Syria (as of December 20, 2018): under Syrian regime control (red); under Kurdish control (yellow); controlled by the rebel organizations in the Tanf enclave (green); controlled by coalition forces (blue); controlled by ISIS (black and lined); uncontrolled by an organization or country (white) (Nours Syrian Institute for Strategic Studies, December 20, 2018).

Impact of the American announcement on ISIS’s activities abroad

Activity in ISIS’s provinces

  • ISIS’s Salafist-jihadist ideology still has power to attract, even if the model of the Islamic Caliphate itself collapsed. However, the concept of a jihad against the “infidels” remains attractive and fuels the continuing existence of ISIS’s provinces in Syria, Iraq and around the globe. The various provinces continue activity at various levels of intensiveness, and both Western countries and local regimes find it hard to subdue them. The provinces which grew stronger during 2018 were Khorasan (Afghanistan-Pakistan) and West Africa (Nigeria, from where ISIS activities trickled into other countries). The Sinai Province as well, which has been under heavy pressure from the Egyptian security forces, proved its ability to survive and initiate terrorist and guerrilla attacks, especially in the northern Sinai Peninsula. The withdrawal of the United States from Syria, and later possibly from Afghanistan, is liable to be perceived (and doubtless to be represented) as a victory, and to encourage ISIS provinces abroad to increase their attacks against local regimes and Western countries.
ISIS-inspired attacks, primarily in the West
  • In 2017-2018 the collapse of the Islamic Caliphate led to a significant decrease in ISIS’s ability to carry out directed attacks abroad, carried out by its own operatives (which are the most complex and deadly). During 2017 and 2018 no such attacks occurred, however, during 2018 ISIS-inspired attacks continued to be carried out abroad by local ISIS supporters, mainly in Western countries (especially France). The number of fatalities was lower than in previous years but the number of ISIS-inspired attacks in 2018 was similar to that of previous years (see graph below). ISIS-inspired attacks continued in the West despite the collapse of the Islamic Caliphate and despite the pressure exerted on ISIS in its core countries.
  • ISIS-inspired attacks are not planned by ISIS headquarters in Syria and do not have organized processes of operational, logistic and intelligence preparations. Most of them are carried out by individuals who identify with and are influenced by ISIS’s ideology. ISIS, however, claims responsibility for the attacks and represents them as part of its war against the coalition countries. In ITIC assessment the sensation of “victory” following the pullout of the American military personnel from Syria (and possibly from Afghanistan) is liable to increase the motivation of ISIS supporters abroad (and the supporters of other jihadist organizations) to carry out terrorist attacks in the West to accompany the American withdrawal as part of a terrorist campaign painful to the West and increasing the image of “victory” over the West.
ISIS-Inspired Attacks, Annual Distribution

ISIS-Inspired Attacks, Annual Distribution

The battle for hearts and minds
  • ISIS gives great importance to its battle for hearts and minds, which also serves its provinces and supporters around the globe. Its media infrastructure was impaired following the collapse of the Islamic State but during the second half of 2018 it showed signs of recovery, changing and adapting to the challenges facing ISIS. Its media outlets are important because they accompany its military activities, ensure that ISIS remains in the public eye, spread its ideology and strengthen its ability to deter the West. The fall of the ISIS enclave in the eastern Euphrates Valley and the weakening of ISIS in Syria might lead to more damage to its media infrastructure (since in ITIC assessment eastern Syria is where ISIS’s central information bureau is located). On the other hand, a rise in the morale of ISIS operatives and the strengthening on the east bank of the Euphrates and in the deserts of eastern Syria will allow it to rehabilitate its media infrastructure and increase ISIS’s capabilities in the battle for hearts and minds around the globe.
ISIS threats during the Christmas season
A threat against the Pope from the Hamas-affiliated al-Abd al-Faqir Institute (Telegram, December 23, 2018).   A threat against the White House (Telegram, December 20, 2018).
Right: A threat against the White House (Telegram, December 20, 2018). Left: A threat against the Pope from the Hamas-affiliated al-Abd al-Faqir Institute (Telegram, December 23, 2018).

[1] First generation ISIS was the Islamic State established in Iraq in 2006 and which spread to Syria in 2011; second generation ISIS was the Islamic Caliphate from the occupation of Mosul in June 2014 until the Caliphate collapsed at the end of 2017; third generation ISIS is the organization's current format of return to a terrorist and guerrilla organization.
[2] According to the Shorter Oxford Dictionary, the definitions of the terms used are the following: degrade means "to reduce in strength or amount," destroy means "to ruin completely or put an end to," defeat means "to gain victory over in battle." Defeat, used by Trump, is more limited in scope than destroy, which was determined by President Obama as the final objective of the campaign against ISIS.

[3] This assessment is limited to the issue of the campaign against ISIS and does not deal with the complex issue of the internal Syrian, regional, international and internal American significance of the president's announcement.