As attacks by ISIS increase in both Iraq and Syria, the upcoming U.S. presidential election offers a turning point for how U.S. foreign policy will seek to address a potential ISIS resurgence. This paper lays out this growing problem and recommends policy, which will be constrained by the outcome of the November election.

Key points

  • ISIS attacks in Iraq and Syria have increased significantly in 2020, demonstrating both a capacity and a willingness on ISIS’s part to retake territory, populations, and resources.
  • In the wake of COVID-19 and the drawdown of U.S. forces, security gaps have worsened, allowing ISIS to move more freely, conduct prison breaks, carry out more sophisticated attacks, and smuggle fighters across borders.
  • The upcoming U.S. presidential election also offers a distinct choice between two candidates: one who will maintain the current disengaged and incoherent status quo and the other who will purportedly maintain a light but effective footprint in the region to counter the remnants of ISIS.
  • The U.S. government must pursue a foreign policy that redirects focus away from a singularly counter-Iran mission, reinvigorates coalition partners to invest and train in the region, surges efforts to support our Iraqi and Syrian partners, and embraces and invests in a diplomacy-first approach.


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As the Trump administration winds down the U.S. presence in Iraq and maintains its smaller footprint in Syria, ISIS is beginning to reconstitute. The timing could not be worse. COVID-19 is ravaging both countries and previous political and economic uncertainties remain high.

With a U.S. presidential election just weeks away, the foreign policy community must grapple with how to prevent an ISIS resurgence, regardless of whether Donald Trump or Joe Biden wins. It is unlikely that this issue will be critical during the final weeks of the campaign, but failure to address this growing resurgence could have a catastrophic effect on efforts to contain ISIS from carrying out sophisticated — and potentially global — attacks. This would reverse the hard-fought gains and investments of all members of the Global Coalition to Defeat ISIS.

President Trump’s own Department of Defense inspector general is warning about the uptick in ISIS attacks, likely as a result of a decrease in direct pressure.1 But the president continues to maintain a one-foot-in, one-foot-out approach, and having already declared victory against the terrorist group, he is unlikely to heed these warnings absent an attack on American soil or a significant attack on U.S. interests abroad.

In Iraq, caretaker Prime Minister Mustafa al-Kadhimi is grappling with a number of issues in addition to an ISIS resurgence. From regular rocket attacks by Iranian-backed militias and a decreasing U.S. presence and diplomatic engagement to a spiraling number of COVID-19 cases, fallout from the global economic and oil crisis, and continuing political protests and unrest, there are multiple threats to stability. While the current situation in Iraq is not a repeat of the one in 2012-13 that led to the rise of ISIS, it certainly has all the makings of a growing and dangerous insurgency. If left unchecked, conditions could spiral out of control.

In Syria, ISIS continues to resurge in areas previously deemed liberated by both the Assad-led Syrian Arab Army and the coalition-backed Syrian Democratic Forces (SDF). The growing insurgency is exacerbated by reports of human smuggling out of ISIS detention centers, uncertainty on what to do with ISIS detainees and their families, the continuation of the Syrian civil war, and competing strategic interests by outside influences.

Though ISIS may be currently unable to mount sophisticated attacks or operations outside of Iraq and Syria, data shows that it is expanding its presence and increasing attacks in both countries. ISIS continues to press forward with online recruitment and remains well-funded, with reserves estimated at between $50 million and $300 million.2 A recent U.N. assessment estimates ISIS manpower to be more than 10,000 fighters,3 while the Pentagon inspector general estimates it is anywhere from 14,000-18,000.4 The conditions that sparked its massive growth in 2014 are unlikely to reoccur, but the coalition should get ahead of the problem while it can. Even a low-level ISIS insurgency in Iraq and Syria will be detrimental to the coalition’s gains and strategic interests in both countries. To stave off what appears to be a growing ISIS insurgency, the U.S. — regardless of which party is in power — must pursue policies that redirect focus away from a singularly counter-Iran mission, reinvigorate coalition partners to invest and train in the region, surge efforts to support our Iraqi and Syrian partners, and embrace and invest in a diplomacy-first approach.

Given indisputable evidence from his current term, President Trump is unlikely to revisit ISIS policy after his re-election. Vice President Biden, by contrast, supports a minimal troop presence and operations in both Iraq and Syria to help combat the remnants of ISIS and ensure that it does not return.5


"While U.S. policy in Iraq has remained laser-focused on Iran and winding down its military presence, ISIS has quietly reconstituted."

Current State of Play: ISIS in Iraq

Over the last few years, Iraq has suffered from a monumental economic crisis, a lack of access to infrastructure and resources to rebuild post-ISIS, massive government corruption, a campaign of militia killings and kidnappings, and now, an intense wave of COVID-19 cases. Instead of working to ease the burden of these crises, the Trump administration has only inflamed them.

The Trump administration, largely at the behest of former National Security Advisor John Bolton, shifted U.S. policy toward Iraq to be encompassed by its larger counter-Iran policy. This came at the expense of the counter-ISIS strategy, particularly once ISIS’s territory in Iraq was declared defeated by former Prime Minister Haider al-Abadi in 2017.6 The administration also dismantled and undercut U.S. diplomatic efforts in the country, pulling out diplomats and aid experts, citing the threat from militias and rocket attacks.7

The U.S. has consistently escalated tensions with Iran and in turn with Iranian-backed militias in Iraq, first by withdrawing from the Joint Comprehensive Plan of Action (JCPOA) and then by waging its maximum pressure campaign, pigeon-holing Iran into a cycle of escalation. In response, Iran began taking action against the U.S. in other places — namely Iraq. Late last year and into 2020, the escalation between the U.S. and Iran peaked, causing the U.S. to retaliate by assassinating Qassem Soleimani and Kata’ib Hezbollah (KH) founder Abu Mahdi al-Muhandis.8 Since January, militias have continued to escalate with rocket attacks against U.S. compounds and strategic sites at a steady pace. The heightened tension led to increased calls from Iraqis for the U.S. to leave; the Council of Representatives actually voted to ask the U.S. to withdraw. Iran-aligned groups like KH have fired scores of missiles toward the Green Zone and other U.S.-occupied areas, though they recently announced a conditional cease-fire against U.S. targets in Iraq, if the U.S. presents a timetable for withdrawal.9

Then came COVID-19, and nearly the entire world came to a standstill. Coalition partners including Canada, the Czech Republic, France, the U.K., New Zealand, Spain, Portugal, and the Netherlands halted training and pulled forces out of Iraq. The U.S. halted and then restarted training, while continuing its scheduled handover of bases like Taji10 and Besmaya,11 as part of the ongoing U.S.-Iraq Strategic Dialogue. This agreement took place in June and August, when the two countries committed to continue reducing the number of U.S. troops in Iraq.

While U.S. policy in Iraq has remained laser-focused on Iran and winding down its military presence, ISIS has quietly reconstituted. In the first quarter of 2020 alone, 566 ISIS attacks were reported in Iraq.12  A recent Terrorism Research & Analysis Consortium (TRAC) assessment found that ISIS claimed 100 attacks across Iraq in August 2020, a 25 percent increase from July.13 There is also mounting evidence that the attacks are becoming more sophisticated, targeting military checkpoints and Iraqi military housing.14 The pandemic and U.S. drawdown have exacerbated these concerns, allowing ISIS fighters to fill the vacuum that troop movements leave behind.15

These statistics paint a grim picture of what the reconstitution of ISIS might begin to look like in Iraq over the coming months without a redirection of U.S. or coalition policy. If the U.S. continues to disengage while Iraq is distracted by the economic crisis, COVID-19, and other competing concerns, ISIS will seize on the opportunity to conduct prison breaks, rebuild its ranks, and retake territory in areas the military or coalition forces have abandoned.


Current State of Play: ISIS in Syria

Apart from a Turkish incursion in 2019 and the regime retaking territory from opposition groups, usually after a deal between Russia, Turkey, and Iran, the territorial lines have remained largely the same over the last year. The regime has shifted its focus north to Idlib Province, the last remaining stronghold of opposition forces, and has ignored the vast areas east of Homs and Damascus. In those regions, an ISIS presence is growing, and there are rumblings of an opposition insurgency in the south.

In the northeast, the U.S. maintains its limited presence — with about 500-60016 troops. The presence has recently been reinforced with 100 more troops, additional jet patrols, and Bradley fighting vehicles after a few dangerous run-ins with the Russians.17 This small presence allows for it to conduct limited counter-ISIS operations with SDF forces and “protect the oil,” the mission touted by President Trump. This number is down from 1,000 last October when President Trump effectively greenlit a Turkish incursion into areas controlled by the SDF, the U.S.’s counter-ISIS partner, north of Raqqa.18 The administration was unable to account for a number of ISIS prisoners that escaped during this Turkish incursion,19 and the SDF continues to deal with prison riots and smuggling attempts.20 Trump also cut funding for assistance programming in Syria, further straining stabilization efforts in areas liberated from the terrorist group.

The president logged a win when special forces teams killed the former ISIS caliph, Abu Bakr al-Baghdadi, last October.21 But the Pentagon also assesses that Baghdadi’s death had no impact on ISIS’s operations, nor did it change the group’s strategy. Furthermore, nearly 10,000 ISIS fighters remain in purgatory prisons, along with tens of thousands of their families in SDF detention camps elsewhere in the northeast. There remains no plan for what to do with these individuals,22 and their detention is growing increasingly unsustainable as Coalition countries scale down assistance and the Syrian civil war continues.

And yet, ISIS continues to grow and increase its attacks in Syria. In regime-controlled areas east of the Euphrates, ISIS appears to be surviving, and in SDF-controlled areas west of the Euphrates, it even appears to be thriving. This growth is a strategy that is reinforced by ISIS’s own messaging. “What you are witnessing these days are only signs of big changes in the region that’ll offer greater opportunities than we had previously in the past decade,” ISIS’s new leader, Abu Ibrahim al-Qurashi,23 stated in May of this year.

COVID-19 has only accelerated this resurgence. The head of Norway’s forces in Iraq, Lt. Col. Stein Grongstad, warned that as the virus “pacifies” others, ISIS will begin to flourish.24 He notes that ISIS fighters live in agricultural areas that are less likely to be exposed to the virus, and Syrian forces are less coordinated than before the COVID-19 crisis. As such, ISIS is again making use of roadside bombs and advanced explosives, and the group knows how to use the unmonitored areas along the Iraqi-Syrian border to its advantage.25

In April of this year, ISIS launched a series of attacks along the border with Iraq against government-held parts of Syria, from Homs to Deir ez-Zor Province. Iraqi intelligence officials report that near the same time, around 500 militants, including some recently-escaped detainees, fled from Syria back into Iraq.26 In one notable attack, ISIS fighters attacked Palmyra, a famous historical site that has been gained and lost (and regained) by the Syrian regime against ISIS several times. The regime was only saved by the Russian Air Force, which drove the fighters out of Sukhna oil field.27 ISIS is also suspected to have blown up a critical Syria gas pipeline in the heart of regime-controlled territory, knocking out power across the country.28

The group also continues to launch a number of attacks against the SDF in the northeast and is working to maintain a visible presence in areas it used to control to stoke fears of a return.29 ISIS has led a steady beat of assassinations, ambushes, and bombings in eastern Syria in 2020, and is responsible for the deaths of a number of regime and SDF forces.

By August, 126 attacks by ISIS across Syria were reported for 2020 — compared to 144 in all of 2019.30

U.S. officials working on Syria continue their efforts to make a legitimate policy out of the minimal resources Trump has left behind. But given the increasing level and sophistication of ISIS attacks, the strain imposed by COVID-19 on already limited resources, and the ongoing civil war, this scramble will only become more difficult.


"Regardless of who wins the presidential election, it is critical for the U.S. government and its foreign policy apparatus to begin reversing current trends and supporting our Iraqi and Syrian partners on the ground."

Projected Way Ahead

While it is unlikely to be a core issue for voters in 2020, the U.S. should nevertheless prioritize tackling the remnants of ISIS before it grows into a full-blown resurgence. A comeback would not only threatens U.S. and coalition interests but would also bring harm to countless Iraqis and Syrians only recently liberated from the group.

U.S. policy must pivot from a mission singularly focused on deterring Iran, restart efforts to encourage coalition countries to invest and train in the region, surge support to Iraqi and Syrian partners, and embrace a diplomacy-first approach. A light U.S.-coalition presence on the ground in both Syria and Iraq will be critical to this endeavor, but coalition countries will be less likely to agree if the U.S. keeps expanding the mission to include a “counter-Iran” component, which most countries have rebuked.

A Trump Second Term

In its first term, the Trump administration largely continued the coalition strategy laid out by the Obama-Biden administration, culminating in Iraq declaring the defeat of ISIS in December 2017 and the SDF declaring its defeat in Syria in March 2019. President Trump has made it clear that ISIS is defeated and that he does not intend to revisit the matter.31

His several attempts to announce a complete withdrawal of the U.S. from northeast Syria in April 2018, December 2018, and again in October 2019, against the wishes of his top military brass and coalition partners, provide compelling evidence. While his own Pentagon and intelligence community are warning against signs of an ISIS resurgence, the president has refused to revisit an increase in the U.S. troop presence or additional resourcing. In fact, he has continually reaffirmed his commitment to pull U.S. troops out of the region, announcing most recently his desire to continue with a troop drawdown in Iraq,32 while Secretary Pompeo has conveyed to Iraqi partners that the U.S. will shutter its embassy if attacks by Iranian-backed militias continue to target Americans.33

It appears highly unlikely, absent an attack by ISIS on the U.S., a critical ally’s soil, or U.S. interests abroad, that the president would revisit or reverse these decisions. We can also expect President Trump to continue ignoring the thousands of ISIS detainees and family members held in Syria. His current policy is that countries must be responsible for the repatriation of their own citizens who have become foreign fighters.34 However, with many other EU countries unwilling to take the same path, the SDF is left without a viable way forward to address the detainee issue.35

A continuation of this current policy will likely push other allies who may be impacted by an ISIS resurgence threat to step up in place of the U.S.’s decrease in diplomacy, funding, and military footprint. This may become more difficult as many coalition countries rely on a U.S. presence to conduct their operations and may contribute less money without U.S. leadership pressing for funds for stabilization activities in areas liberated from ISIS. Trump will also likely continue to disengage on diplomatic efforts, forcing other countries — possibly our adversaries — to fill the vacuum of U.S. leadership in the region.

A Biden Presidency

Vice President Biden has vocally opposed President Trump’s decisions since he declared victory over ISIS and began pulling U.S. troops out of Syria.36 He also expressed that the president’s decision to “secure the oil” would be a recruitment mechanism for ISIS in years to come.37 Recently, Biden conveyed that he wants to end forever wars but would continue to support a light U.S. military footprint for special operations against ISIS and other terror threats in the region.38

During his political career, Biden has a proven track record of supporting diplomatic initiatives and is known for his ability to charm world leaders.39 During this campaign, he has committed to restoring U.S. leadership in the world, reaffirming its alliances, and “drawing on the full array of [U.S.] strengths.”40 He has also committed to focusing on counterterrorism, while steering clear of “unwinnable conflicts.”41

Based on this messaging, we can expect a Biden-led U.S. to reinforce its commitment to partners on the ground in Iraq and Syria and to reinvest in necessary resources that will expand counter-ISIS raids against cells popping up in SDF areas in the northeast and down along the Euphrates river. The U.S. would also likely resume its leadership role in the Global Coalition to Defeat ISIS, renewing a commitment to critical stabilization funding for liberated areas in both Iraq and Syria and shoring up diplomatic efforts to encourage other coalition countries to do the same. A Biden presidency may also take on a greater role in determining what to do with ISIS detainees, whether it be helping countries repatriate their citizens or fundraising to establish more sustainable detention facilities.



Regardless of who wins the presidential election, it is critical for the U.S. government and its foreign policy apparatus to begin reversing current trends and supporting our Iraqi and Syrian partners on the ground, who are at the forefront of these attacks. Both candidates have made their positions on this issue clear.

Under a continuation of the Trump administration, ISIS is likely to capitalize on pressing economic and public health challenges in Iraq and Syria, to continue to grow, and to carry out more attacks in both countries. Under a Biden administration, it can be inferred from his campaign messaging that he would reinvigorate the coalition, restore U.S. alliances and leadership, and recommit to ensuring that ISIS remnants are unable to threaten key global interests.



1. Sean W. O’Donnell, Stephen Akard, and Ann Calvaresi Barr, Operation Inherent Resolve, (Washington: U.S. Federal Government, 2020),18,

2. Ibid, 18.

3. United Nations Security Council, Eleventh Report of the Secretary-General on the Threat Posed by ISIL (Da’esh) to International Peace and Security and the Range of United Nations Efforts in Support of Member States in Countering the Threat, (New York City: United Nations, 2020), 3,

4. Ellen Ioanes, “A Scathing New Pentagon Report Blames Trump For the Return of ISIS in Syria and Iraq,” Business Insider, August 8, 2019,….

5. Steve Beynon, “Biden Says US Must Maintain Small Force in Middle East, Has No Plans for Major Defense Cuts,” Stars and Stripes, September 10, 2020,….

6. Margaret Coker and Falih Hassan, “Iraq Prime Minister Declares Victory Over ISIS,” The New York Times, December 9, 2017,….

7. Robbie Gramer, “State Department Outlines Dramatic Scale-Down of U.S. Presence in Iraq,” Foreign Policy, December 17, 2019,….

8. Matthew S. Schwartz, “Who Was The Iraqi Commander Also Killed In The Baghdad Drone Strike?,” National Public Radio, January 4, 2020,….

9. Louisa Loveluck, "Iran-backed militias announce ‘conditional’ cease-fire against U.S. in Iraq," The Washington Post, October 12, 2020,….

10. Louisa Loveluck, “U.S.-led Coalition to Withdraw Hundreds of Troops From Smaller Bases in Iraq,” The Washington Post, March 16, 2020,….

11. Chad Garland, “US-led Coalition to Turn Over Training Base South of Baghdad to Iraq,” Stars and Stripes, July 24, 2020,….

12. Michael Knights and Alex Almeida, “Remaining and Expanding: The Recovery of Islamic State Operations in Iraq in 2019-2020,” Combating Terrorism Center, May 2020,….

13. Hollie McKay, “ISIS Launched More Than 100 Attacks in Iraq in August, a Sharp Uptick From Previous Month,” Fox News, September 3, 2020,….

14. Qassim Abdul-Zahra, Bassem Mroue, and Samya Kullab, “IS Extremists Step Up as Iraq, Syria, Grapple With Virus,” AP News, May 3, 2020,

15. “IntelBrief: Recent Islamic State Attacks Demonstrate Its Durability and Resilience,” The Soufan Center, May 13, 2020,….

16. Eric Schmitt, “Top General in Middle East Says U.S. Troop Levels Will Drop in Iraq and Syria,” The New York Times, August 12, 2020,….

17. Eric Schmitt, “U.S. Sending More Troops to Syria to Counter the Russians,” The New York Times, September 18, 2020,….

18. Joseph Votel and Elizabeth Dent, “The Danger of Abandoning Our Partners,” The Atlantic, October 8, 2019,….

19. Greg Norman, “More Than 100 ISIS Prisoners in Syria Are on the Loose Following Turkey’s Invasion, US Envoy Says,” Fox News, October 23, 2019,….

20. Abdullah al-Ghadhawi, “ISIS in Syria: A Deadly New Focus,” Center for Global Policy, April 28, 2020,

21. Jim Garamone, “Central Command Chief Gives Details on Baghdadi Raid,” U.S. Department of Defense, October 30, 2019,….

22. Elizabeth Dent, “The Unsustainability of ISIS Detentions in Syria,” Middle East Institute, March 12, 2019,

23. Translated by Hassan Hassan, Center for Global Policy; Gayle Tzemach Lemmon, “ISIS Is Using Coronavirus to Rebuilt Its Terrorism Network in Iraq and Syria,” NBC News, May 28, 2020,….

24. Harald Berg Sævereid, “IS Får Drahjelp av Coronaviruset: Terrorbevegelsen Bygger Seg Opp Igjen,” Verdens Gang, May 13, 2020,….

25. Ibid.

26. Abdul-Zahra, Mroue, and Kullab, “IS Extremists Step Up.”


28. “Syria Gas Pipe Explosion Suspected to Be IS Attack, US Says,” Sky News, August 24, 2020,….

29. Al-Ghadhawi, “ISIS in Syria.”

30. Ibid.

31. Yuliya Talmazan, “U.S. Troops Leaving Syria for Western Iraq as Kurds Look to Withdraw Amid Cease-fire,” NBC News, October 20, 2019,….

32. Zeke Miller, “Trump Planning to Withdraw More US Troops From Iraq,” The Associated Press, Military Times, September 9, 2020,….

33. Isabel Coles and Michael R. Gordon, “U.S. Warns Iraq It Is Preparing to Shut Down Baghdad Embassy,” The Wall Street Journal, September 27, 2020,….

34. Vanessa Romo, “European Leaders Reluctant to Meet Trump’s Demands to Take Back Captive ISIS Fighters,” National Public Radio, February 18,….

35. Ibid.

36. Tom McCarthy, “Biden Warns ISIS Fighters Will Strike US Over Syria Withdrawal,” The Guardian, October 15, 2019,….

37. Ibid.

38. Hans Nichols and Margaret Talev, “Biden, Troop Levels, and the 9/11 Legacy,” Axios, September 11, 2020,….

39. Michael Crowley, “’Strategic Empathy’: How Biden’s Informal Diplomacy Shaped Foreign Relations,” The New York Times, July 5, 2020,….

40. Joseph R. Biden Jr., ”Why America Must Lead Again,” Foreign Affairs, March/April 2020,….

41. Alex Ward, “Trump and Biden Want You to Believe They’re More Anti-War Than They Are,” Vox, September 21, 2020,….



Cover photo: An Iraqi fighter with the Popular Mobilization Forces inspects the site of an ISIS attack, a day earlier, on a unit of the paramilitary force in Mukaishefah, north of the capital, on May 3, 2020. (Photo by AHMAD AL-RUBAYE/AFP via Getty Images)

Contents photo: This picture taken on March 24, 2019 shows a discarded ISIS flag lying on the ground in the village of Baghouz in Syria’s eastern Deir Ez-Zor Province near the Iraqi border, a day after the group’s “caliphate” was declared defeated by the U.S.-backed Kurdish-led SDF. (Photo by GIUSEPPE CACACE/AFP via Getty Images)

Anti-ISIS operations involving the Iraqi army, police, and Popular Mobilization Forces in Kirkuk on June 22, 2020. (Photo by Ali Makram Ghareeb/Anadolu Agency via Getty Images)

Democratic presidential candidate Joe Biden delivers remarks on the Trump administration’s recent actions in Iraq on January 07, 2020 in New York City. (Photo by Spencer Platt/Getty Images)


About the Author

Elizabeth Dent is a non-resident scholar with the Middle East Institute’s Countering Terrorism and Extremism program. She previously served as the Special Assistant to the Special Presidential Envoy to the Global Coalition to Defeat ISIS, supporting diplomatic engagements with coalition countries and working with local partners on the ground in Iraq and Syria to accelerate the campaign against ISIS. Elizabeth has been working on ISIS at the Department of State since 2014, where she helped coordinate and implement the counter-ISIS messaging strategy, and later covered ISIS in North Africa for the coalition office. She began her career at the Bureau of Diplomatic Security, where she provided policy guidance and support to bureau leadership regarding best security, strategic, and operational practices.