After years under rebel control, the Syrian city of Aleppo has now effectively fallen to pro-government troops and army forces. Thousands of residents are now being bussed out of the city and face an uncertain future.

The loss of Aleppo leaves Syria’s opposition at one of its weakest points since the nation’s peaceful protests turned into an armed uprising in 2011. Rebel groups now lack control of any major urban center and have dim prospects for retaking significant territory anytime soon.

Meanwhile, Bashar Assad’s regime has had an enormous reversal of fortunes from its imperiled position just over a year ago. Supported by Russian airstrikes and foreign-backed militias, Assad carried out a sustained and devastating assault on Aleppo that has now culminated in the effective retaking of the city.

But Aleppo falling to government control is by no means an end to the war. Assad still has only a tenuous control over much of the country ― as shown this week when Islamic State militants retook the ancient city of Palmyra from government forces. There are also numerous rebel strongholds throughout the nation, which include groups that continue to receive foreign support.

Instead of an end to Syria’s war, the conflict and the groups involved in it will likely now shift to adapt to the current situation. One change may be that more extreme elements of the opposition make gains among the rebels, as fighting shifts to areas such as Syria’s Idlib province, where such groups are more prominent.

“The fall of Aleppo is likely to strengthen hardline Islamists, who are less likely to throw in the towel and give up, and who are also better suited to waging an underground campaign,” Aron Lund, a fellow with the Carnegie Endowment for International Peace’s Middle East Program, told The WorldPost.

Extremist groups like Jabhat Fateh al-Sham ― a recently rebranded version of the al Qaeda-linked Nusra Front ― are also less reliant on foreign support than the more moderate factions supported by western powers like the United States.

Omar Sanadiki / Reuters Buses are seen parked in Aleppo's government controlled area of Ramouseh, as they wait to take civilians and rebels from eastern Aleppo on Thursday.

Rebels have already signaled that they want a greater response from foreign powers. A senior opposition figure made a plea for increased support from Gulf states on Wednesday, saying the present situation requires a ramping up of military aid.

It’s currently unclear what the response from western and regional powers will be to the loss of Aleppo. U.S. Secretary of State John Kerry condemned the assault on the city as a “massacre” on Wednesday, but made no mention of any decisive action the United States would take in response.

As the war shifts away from Aleppo, Lund says it is also possible that some hardline groups may increasingly resort to guerrilla tactics such as car bombings and targeted killings. But despite the ability of these tactics to prolong the war, they have limited power to actually turn the tables in favor of the opposition.

“As a political project, such an underground war would not seem very inspiring to those opposition members who hope for something more than martyrdom and mayhem,” Lund says.

“A guerrilla campaign that has no other goal than prolonging the war eternally won’t keep pragmatists on board for long. It will end up being a jihadi project and it will lose most of its international support.”

Once Aleppo is secured, there are a number of other areas of the country that pro-government forces may target militarily. Areas such as Idlib province, ISIS-controlled eastern Syria and rebel-held territory near Damascus may each face a similar offensive to the one that killed thousands of people and left much of Aleppo in ruins.

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