On September 19, U.S. Central Command announced a successful raid in Syria that “resulted in the death of a senior ISIS operative … Omar Abdul Qader,” who was “actively seeking to attack the United States.” Six years after what was supposed to be its obliteration, the Islamic State is once again rearing its ugly head in its old stomping grounds, which it “ruled” as a “caliphate” from 2014 to 2018 with all the severity of 7th-century Islam.

The Islamic State (IS) first arose in a power vacuum after President Barack Obama pulled U.S. forces out of a tottering, newly reconstituted Iraq. Now, IS has re-emerged in another vacuum, created by the December 2024 fall of Syria’s Assad regime.

But Assad’s weak, unpopular regime was only part of the puzzle. By the time President Trump stamped out IS resistance in 2019, Syrian territory was divided between the Russia-backed Assad regime, Turkish-backed Islamic rebels in the northwest, and a U.S.-backed Kurdish region in the northeast. It took coordination from all these powers to drive the last remnants of IS into hiding.

Now, the Islamist rebels from the northwest have assumed power in Damascus, but they can no more project power throughout the entire country than Assad could. “This area is too big, and the Damascus government is unable to control it,” said Goran Tel Tamir, a commander in the Kurdish Syrian Defense Forces (SDF), which controls northeast Syria.

Yet IS in Syria remains a far weaker version of itself. Unable to hold territory, the group has adopted decentralized guerrilla tactics, operating with small cells of armed men in civilian clothing, who attack, then blend back into the local populace. IS militants obtained fresh weapons from raiding arms depots left behind after the Assad regime collapsed, so that “everyone has one AK-47 and an explosive device,” said SDF spokesman Siymend Ali.

Through the end of August, IS militants perpetrated 117 attacks in northeast Syria, far more than the 73 attacks they carried out in all of 2024. In a May 18 car bomb attack, IS killed five members of the new Syrian regime’s armed forces, and it has plotted operations as far away as Damascus.

On June 22, a suicide bomber attacked a Greek Orthodox church in Damascus, killing 25 and injuring 63, the largest attack on Syrian Christians since the American Civil War. Although it did not take immediate credit, Syrian authorities claimed IS was behind the attack.

However, most of the IS attacks have been directed against the much closer power, the U.S.-aligned SDF. The IS power base is in the eastern Deir Ezzour province, a desert area the size of Maryland, where at least part of the conservative Sunni Arab population sympathizes with their cause.

The SDF is still responsible for guarding thousands of prisons that house nearly 50,000 IS fighters, plus their families. This responsibility stretches its forces thin in other areas, such as responding to threats from Turkey or patrolling for IS militants extorting locals. On at least one occasion, IS fighters attacked a prison camp and were able to successfully free the detainees inside.

After the Assad regime fell, there was high-flown discussion of the SDF merging with the new government, but that has not happened yet. In fact, Kurdish forces and government-backed forces confronted each other in August in the northwestern city of Aleppo. The SDF also has little faith in the new Damascus government, since they remember that Syrian President Ahmed al-Sharaa was once aligned with IS before he switched his allegiance to al-Qaeda.

Between the weakened regime in Damascus and the beleaguered Kurdish organization in the northeast, IS militants clearly believe the region is ripe for their reappearance.

This comes as the U.S. plans to whittle down its forces supporting the SDF. After the October 7 terror attack, the U.S. increased its troop presence in Syria to 2,000. Since April, the U.S. has whittled that number down by about 500 and may reduce it to below 1,000. The September raid demonstrated that the U.S. still maintains the ability to execute operations against IS, but that could change if the resurgent movement regains strength. One thing is certain: the Middle East remains a very dangerous place.