Iraqi civilians, escorted by soldiers, reach the Bab Sinjar neighborhood at the entrance of old city in western Mosul, Iraq, on June 25 (XINHUA)

The so-called "Islamic State of Iraq and al Shams" (ISIS) has suffered one defeat after another on the battlefield in Iraq and Syria over the past several months.

The Iraqi Government started the battle to recover the city of Mosul last October. Now the campaign is drawing to a close. On June 18, Iraqi government forces pushed the battle line forward to the old urban area of Mosul, the last outpost ISIS held in the city.

ISIS as a tangible entity will inevitably be disassembled eventually. But it is too early to be optimistic about the future situation of international efforts to counter terrorism. In a post-ISIS era, the world might continue to be dogged by more elusive terror threats.

Battleground retreat

Thanks to the strengthened international effort on fighting terrorism, ISIS has suffered great losses in terms of territory and personnel. The semi-military force is very likely to retreat to its former status as an underground jihadist group.

ISIS was on the rampage in Iraq in 2014. According to statistics by RAND Corp., ISIS occupied 13 percent of the country's territory (58,372 square km), in which the terrorist organization controlled around 19 percent (6.3 million) of Iraq's total population. A number of important cities fell into the hands of ISIS, including Ramadi, Mosul, Kirkuk and Tikrit.

By the beginning of this year, these figures had changed dramatically. The area ISIS controlled had shrunk to 15,682 square km, and the population in its realm had also decreased to 1.1 million.

In the Mosul campaign, Iraqi government forces imposed a heavy blow on ISIS. Mosul is Iraq's second largest city and oil industry center. The city has a special symbolic significance for ISIS because ISIS chief Abu Bakr al-Baghdadi proclaimed the establishment of the group in Mosul in 2014.

In Syria, ISIS is also in an unfavorable situation. The organization's "capital," Raqqa, has been besieged for months.

Furthermore, ISIS sphere of influence in Central Asia, South Asia and North Africa has diminished greatly due to joint action by various governments.

Meanwhile, it faces a shortage of funds. Members of the international community reached consensus on cutting off the group's funding, and the strategy has proven effective. ISIS was the richest terrorist organization in the world. It once controlled many oil fields, which provided the group with huge revenue. Moreover, it received a large amount of donations from sympathizers and supporters across the world. As the Iraqi Government recovers more territory, and the influx of foreign jihadists drops sharply, ISIS has taken a blow to its funding sources. Reportedly, the salaries paid to ISIS militants have dropped by 50 percent, and their morale has sunk.

After many battles, ISIS has sustained serious losses of combatants, and a number of ISIS commanders have been killed. More importantly, the Russian military announced on June 16 that it might have killed al-Baghdadi in an airstrike on Raqqa. If proven to be the case, it will be a big blow to the survival of ISIS. According to media reports, the international coalition has annihilated as many as 20,000 ISIS militants since it launched military action against the organization.

Regroup and reorganize

Suffering such great defeat, ISIS looks set to adjust itself to adapt to the new situation and will, thereby, continue to pose a threat to the world.

ISIS is likely to simplify its organization and might change its tactics. It has built a highly-centralized caliphate under al-Baghdadi, with executive departments performing various functions. But the organization's multilayer administrative structure will be trimmed as ISIS is all but destroyed as a distinct entity. Its high-level leaders will endow middle-level combat commanders with more flexibility to launch terror attacks.

Asymmetric tactics might be more frequently used by ISIS as a major retaliatory measure. The international community must keep being vigilant as the organization may break up into parts, sending small groups of jihadists to conduct guerrilla warfare and harassing attacks, including assassinations and suicide bombings, against military and police targets or even civilians.

ISIS militants are likely to regroup with other jihadist groups. ISIS once had conflicts with Al-Qaeda and the Taliban in vying for influence in Central Asia and the leading position in the global jihadist movement.

It is reported that ISIS has been in talks with Al-Qaeda. As early as September 2015, Al-Qaeda chief Ayman Zawahiri hinted at possible cooperation with ISIS. If the two terrorist organizations join hands, the world will face a more complex situation in countering terrorism.

ISIS' continuing setbacks in Iraq and Syria might force it to expand its network and enroll jihadists in peripheral countries.

The flow back of jihadists from the Middle East to Western countries is also worth noting. At its height, around 40,000 foreign jihadists were fighting for ISIS on the battle lines in Iraq and Syria. Since last year, some of the remaining foreign jihadists have either returned to their home countries or moved to a third country. Some of them have conducted local attacks, while others are hiding themselves awaiting an opportunity.

Afghanistan's experience in previous years shows that foreign jihadists who had gained battle experience and made many "friends" within their terrorist organization can rapidly grow to become a new threat. Both Zawahiri and al-Baghdadi participated in jihadist movements in foreign countries such as Afghanistan.

In recent times, the foreign jihadists fighting in Iraq and Syria greatly outnumbered those who were in Afghanistan in the 1990s. With the backflow of jihadists, it has emerged that the terror attacks in Europe in the last two years were connected with the jihadists who had returned from the Middle East.

As ISIS declines, other terrorist organizations might rise. In future, the leading role of ISIS might be taken by another terrorist organization such as Jabhat Fatah al-Sham, an opposition force in Syria, which used to have relations with Al-Qaeda and later announced its separation from the organization. Currently, Jabhat Fatah al-Sham has annexed some opposition factions and holds an advantageous position among opposition forces in Syria.

An Iraqi boy walks past a military vehicle in western Mosul on June 25, as Iraqi forces battling ISIS militants continued in the heavily populated old city (XINHUA)

Total victory far from assured

Military triumph over ISIS doesn't mean a complete counter-terrorism victory. Many challenges need to be tackled.

It remains difficult to rein in the expansion and spillover of ISIS beyond the Middle East. Although ISIS has suffered a heavy blow in its core territory, the organization has never stopped making trouble in Europe, Central Asia and Southeast Asia.

The geopolitical struggle between the United States and Russia as well as other regional powers has a crucial influence on the fight against ISIS. Today, these nations could put aside their disputes and work together because ISIS has become the biggest terror threat to the world. But it doesn't mean they will continue cooperation if ISIS is defeated. The Middle East remains an arena of concern for world powers such as the United States and Russia; regional powers like Saudi Arabia, Iran, Turkey and Israel; and Islamic Sunni and Shiite factions as well as the Kurds. Fighting terrorism is often used as a way to suit their respective objectives.

Maintaining international cooperation is the only way to defeat ISIS and prevent the rise of another terrorist organization in the region.

The author is an assistant researcher of Security and Strategy at the China Institutes of Contemporary International Relations

Copyedited by Chris Surtees

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