The enduring ramifications of ISIS’s explosive rise to power in Syria and Iraq back in 2014 cannot be understated. The terrorist group’s swift expansion triggered escalation in conflict theaters around the world, particularly in Africa, while its years-long campaign of debilitating terror attacks in the West amid mass refugee flows to Europe fueled a dramatic rise in populist politics that provoked divisions within Europe and the North Atlantic Treaty Organization (NATO) as well as sharp discord within domestic politics in multiple capitals. Acute government failure in Iraq and Syria’s collapse into chaos provided the conditions necessary for the emergence of the biggest, wealthiest, and deadliest terrorist organization in history — and the world changed as a result.

The United States' indispensable role in containing ISIS

While ISIS’s territorial “state” was successfully defeated in Syria four years ago, the group sustains an active and dangerous insurgency. Facing down that considerable and persistent challenge are 900 U.S. troops and our local partners, the Syrian Democratic Forces (SDF). With this light footprint approach and working “by, with, and through” the SDF, U.S. forces are having a vitally important impact on containing and degrading ISIS’s capacity to resurge. So far in 2023, American military personnel have conducted at least 44 high-profile operations targeting senior ISIS operatives — a 15% increase on 2022. Among those killed or captured this year are senior ISIS leaders responsible for plotting terrorist strikes in Europe and commanders dedicated to planning major prison break out operations.

The results of our persistence against ISIS’s insurgency are beginning to show, with attacks in U.S.- and SDF-administered northeastern Syria and next door in Iraq down 37% and 80%, respectively, versus 2022. This is all good news, of course, but there is a problem. While ISIS is being effectively contained and degraded in Iraq and northeastern Syria, it appears to have the upper hand in central and southern Syria — areas controlled by President Bashar al-Assad’s regime. Over the past 18 months, ISIS has expanded its reach within regime areas of Syria, re-emerging in the south and sustaining operations in vast swathes of Homs, Hama, Raqqa, and Deir ez-Zor governorates. In these regime areas, ISIS is back to controlling territory too, having recently defeated a six-week offensive by Syrian and Russian forces in a lightly populated stretch of the central desert. ISIS also just completed its most aggressive and deadly month of attacks in over three years in regime-held areas, killing at least 115 people in April. In short: the regime is losing and ISIS is winning.

Despite having faced at least 83 drone and rocket attacks by Iranian-directed proxies since 2021 and now also dealing with increasing acts of Russian brinkmanship in the skies above Syria, U.S. forces are clearly the indispensable factor in the ongoing campaign against ISIS. Since coming into office in 2021, President Joe Biden has acknowledged this simple truth, and his administration has therefore consistently supported the U.S. troop presence in Syria. A good thing too, given the scale and complexity of the problem, our proven track record for success, and the enormous and unprecedented challenges associated with holding more than 10,000 ISIS detainees and 55,000 linked women and children in a network of makeshift prisons and camps in Syria’s northeast.

The dangers stemming from normalizing Assad

Yet despite the Biden administration’s clear acknowledgment that countering ISIS and its associated challenges in Syria is a vital U.S. interest, the entire effort seems headed for a dangerous and premature end thanks to Washington’s broader disinterest in Syria policy. In recent months, multiple leading governments in the Middle East has been proactively normalizing their relations with the Assad regime, despite the latter’s atrocious human rights record and refusal or failure to resolve any of the underlying causes and drivers of instability in Syria. The Biden administration’s diminishing responses to such acts of normalization — from outright opposition in 2021 to calls last month to “get something in return” and now to being “encouraged” — has been deplorable, but officials from those governments reaching back out to Assad have told this author they have been privately encouraged to engage by Biden officials, not to avoid doing so.

Thus, through a combination of overt inaction and covert action, the Biden administration appears to be facilitating Assad’s normalization. In doing so, the administration is actively eroding the U.S. government’s public and principled position on Syria — advocating for substantive political change via a nationwide cease-fire, a political settlement, justice and accountability, and eventual nationwide elections. In other words, we are violating our stated policy, destroying our credibility and leverage, and ultimately empowering the 21st century’s most notorious war criminal in the process. Left unchecked, this baffling and illogical approach to Syria is paving a path toward an eventual and unpredictable exit from Syria. Clearly aware of this, our SDF partners just announced their readiness to engage the Syrian regime and negotiate a deal.

Since the late 1990s, the Syrian regime has embedded within, manipulated, and weaponized jihadists to further its own domestic and foreign policy agendas. Its record of doing so has been extensively documented and is certainly well known to the U.S. government. Hundreds of our own servicemen and women would still be alive today, had it not been for Syria’s direct support to and facilitation of al-Qaeda in Iraq. So, the prospect of a hasty U.S. exit from northeastern Syria should send shudders down policymakers’ spines. At the blink of an eye, 65,000 ISIS-associated men, women, and children currently in prisons and camps would find themselves under regime control, while the regime’s already failing efforts to contain ISIS in 60% of Syria would be dramatically weakened by having to do so in 90% of the country.

Given the debacle witnessed in Afghanistan in August 2021, it is hard to understand why anyone in the Biden administration would want to envision such a scenario playing out in Syria — particularly with Biden running for re-election in 2024. In the recent past, some defenders of the administration’s minimalist, hands-off approach to Syria policy have argued that even if the U.S. were forced to withdraw militarily from northeastern Syria, we could still retain the ability to conduct a counter-ISIS campaign via an arrangement for access with the regime and Russia. Such a proposal was barely logical two years ago, but it is a fantasy today. Leaving Syria would spell a permanent end to our effective efforts to combat ISIS and the transfer of those responsibilities to actors that have consistently failed or refused to do so.

This would be a catastrophic mistake — and an irreversible one at that. When the Obama administration decided to withdraw from Iraq in 2010, it set in motion events that led directly to ISIS’s dramatic resurgence in 2014. But at least we maintained healthy and constructive relationships in Baghdad and Erbil that allowed us to return when ISIS took over half the country. An exit from Syria would provide no second chances.

Worse still, Syria’s crisis is not and has never only been about ISIS. The terrorist group’s meteoric rise and persistence is merely one of many destabilizing symptoms of the Syrian crisis. And like ISIS, the unconditional and unchallenged normalization of Assad’s regime will exacerbate the many other symptoms too, from mass displacement and long-term refugee populations, economic collapse and humanitarian suffering, rife and intractable violence and organized crime, institutionalized corruption and warlordism, and multiple overlapping geopolitical conflicts playing out on Syrian soil and over Syrian skies.

Matching U.S. deeds to its rhetoric on Syria

If the Biden administration were to live up to its campaign promise to deal more determinedly to resolve Syria’s crisis and prioritize its millions of victims, it would have behaved very differently over the past two years. Instead, it has displayed little interest in doing more than symptom containment. Through that all, the campaign to counter ISIS is the one issue that has retained consistent presidential-level support, but the current disinterest in pushing back against Assad’s normalization will undoubtedly kill off that line of effort too.

Within the halls of the Defense Department and U.S. Central Command, concern over this state of affairs is acute. But those concerns were present in the lead up to President Biden’s decision to leave Afghanistan, and they did little to change the calculus in the Oval Office. Bashar al-Assad is living his best days in 2023, toasting his survival on the ashes of his victims — but within the small community of optimistic actors in Syria, ISIS is sitting pretty comfortably too.


Charles Lister is a senior fellow and the Director of the Syria and Countering Terrorism & Extremism programs at the Middle East Institute.

Photo by DELIL SOULEIMAN/AFP via Getty Images

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