US President Donald Trump announced this week that he has decided to pull American troops out of Syria because the ISIS terrorist group is now "defeated". The superpowers troops and advisers form a key part of an international military coalition that backs the Syrian Democratic Forces (SDF) -- made up of Kurdish and Arab fighters -- in ongoing battles against the jihadists. So has ISIS really been defeated? - Fighting continues - After conquering vast swathes of Syrian territory in 2014, IS has suffered numerous setbacks over the past two years, due to separate offensives by the SDF and Syrias national military. The jihadists have been confined to a few pockets of territory in eastern Syria and the countrys vast Badiya desert, which extends from Homs province to the Iraqi border. Despite losing almost all the territory it conquered, IS maintains a strike capability, as seen in multiple deadly attacks in Syria in recent months. It has also resisted to the last man offensives designed to recapture its remaining strongholds. On Wednesday, the jihadist group carried out a new counter-attack, according to the Syrian Observatory for Human Rights, a Britain-based war monitor. It hit SDF positions near Hajin, which had been the jihadists eastern stronghold, until it was retaken last week by the Arab-Kurdish forces. "Both sides continue to engage in intense fighting east of the Hajin area", Observatory head Rami Abdel Rahman told AFP on Thursday. IS, which retains control of other areas near Hajin, fiercely defends its presence in this part of Deir Ezzor province, where some 2,000 jihadists are cornered, according to the coalition fighting the group. The IS combatants, which know the area better than their enemies, have non-Syrian combatants within their ranks, according to the SDF. There are "top-ranking" leaders among them. "A mini-army of several hundred fighters... has been assembled by ISIS there, including some of its best snipers," according to Nicholas Heras, an analyst at the Center for a New American Security. ISIS has also regularly attacked the Syrian regime forces and its allies in the Badiya desert. - Dormant cells - ISIS retains numerous dormant cells, which it has drawn on to launch suicide attacks in cities and areas retaken by its enemies in Syria. The group was dislodged from Raqqa, the former "capital" of its self-proclaimed caliphate, last year. But strict security measures adopted by the SDF remain in place, due to fears of militant infiltration. "They have nothing to lose," said Abdel Rahman. "After the attacks against their strongholds, thousands of ISIS fighters have mutated into dormant cells spread throughout reclaimed areas, from Minbej in the north to Deir Ezzor in the east. "These cells constitute an alternative army... which seeks to sow chaos and insecurity in the areas controlled by the SDF", he added. Several hundred ISIS fighters detained by the SDF in camps represent a potential force that the extremists could yet mobilize once more. Asked by AFP whether the SDF may let down its guard of these captives in reaction to Trumps decision -- perceived as "treason" by thousands of Kurds -- SDF spokesman Mustafa Bali replied "no comment". - Attacks abroad - The blows suffered by the jihadists have not prevented them from carrying out attacks outside Syria, particularly in countries that are part of the international military coalition. IS claimed a mass shooting at a Christmas market in the French city of Strasbourg on December 11 that killed five people -- the latest in a long line of attacks that have targeted various cities. ISs propaganda arm Amaq said an ISIS fighter had been responsible for stabbing and killing a person in November in Melbourne, Australia. IS also claimed an attack that killed at least six in the Afghan capital Kabul in November. Analysts believe that a withdrawal of US troops will only inspire a new lease of life for the jihadist group, also known as ISIS. "President Trump is putting the cart before the horse, because ISIS has not been defeated in Syria," Heras said.