BEIRUT, Lebanon -- A major offensive by the United States, its allies and, notably, with some of its rivals as well to capture the northern Syrian city of Raqqa is gathering momentum and shaping up to be one of the most decisive battles of the Syrian war.
The liberation of Raqqa, de facto capital of the Islamic State's self-declared caliphate, may take months. The retaking of the city and other Islamic State strongholds in northern Syria such as al-Bab and Deir ez-Zor by an alliance of powers that have different objectives in Syria could disintegrate into other conflicts that have been set aside for the strategic imperative of crushing the jihadist group on the battlefield.
That will not be the end of IS, which is expected to go underground and unleash terror attacks across the globe while it regroups and rebuilds its many-tentacled organization.
The Obama administration began planning the offensives against Raqqa and Mosul in northern Iraq, the largest city held by the jihadists, in January 2016. Then-U.S. Defense Secretary Ashton Carter set a target to take both cities by the end of that year.
That did not happen and the push against Mosul, 279 miles to the east of Raqqa and three times as large, only began Oct. 17. The battle there is still raging, with Iraq's future as a unitary state hanging in the balance, as indeed Syria's does ultimately.
Geopolitical rivalries among the major international and regional powers engaged in Syria were to blame for the delay in launching the multipronged push against Raqqa. The battle moved into high gear on Feb. 4 amid a sharp escalation in U.S. airstrikes, later joined by the Russian Air Force in an awkward collaboration that may presage a unified campaign against the jihadists.
The United States backs some rebel groups fighting the regime of Syrian President Bashar al-Assad, along with Turkey and Saudi Arabia, but its key objective is to obliterate IS. As Syrian rebels point out, Assad's beleaguered regime has slaughtered 10 times as many Syrians as IS has during Syria's six years of conflict, which now encompasses several separate wars.
Russia and Iran back Assad but have widely divergent strategic objectives in Syria, although they also perceive IS as a threat and want it eliminated.
Turkey, which once sought to oust Assad, now under Russian influence and the lure of a new strategic alliance, wants him to stay in power in this ghoulish gavotte in Syria.
Former President Barack Obama strove to avoid a major deployment of U.S. forces on the ground in Syria but his successor Donald Trump, more hawkishly inclined, may decide to reinforce the few hundred U.S. special forces active there.
Trump and his inner circle have "little political baggage and are thus freer to change existing policy to seek a resolution of the conflict," observed David Kilcullen, a former Australian Army lieutenant-colonel and counterinsurgency expert who was a senior adviser to U.S. Army Gen. David Petraeus in Iraq in 2007-08.
"This is what makes the fighting around Raqqa so strategically important," he wrote in The Australian newspaper in December. "The outcome of the Raqqa battle will set the tone of [the Trump administration's] relationship with both countries, which in turn will shape much of the global security environment for the next several years."
Trump has ordered his military chiefs to reinforce the 500 U.S. combat advisers currently in Syria and draw up plans for a conventional military buildup, which U.S. military sources said could include a 2,000-person brigade of the famed 82nd Airborne Division.
Trump may also, for the first time, unleash long-range attacks by U.S. B-52 and B-2 strategic bombers against targets in Syria, as the United States did against IS targets in Libya in January. That, however, would risk heavy civilian casualties in Raqqa.
There are an estimated 250,000 civilians trapped in Raqqa under brutal IS occupation. If the Russian Air Force's relentless pounding of eastern Aleppo for weeks on end in late 2016 is any guide, the civilian body count could be high.
"Will ISIS defend Raqqa to the end, as it is doing in Mosul and al- Bab?" asked Turkish security analyst and columnist Metin Gurcan, who served as a military adviser in Afghanistan and Iraq, on Feb. 13. "ISIS defenses and fortifications in Raqqa and its periphery suggest it will be a fight to the end."
As the final phase of the offensive against Raqqa unfolds, U.S. Army Lt. Gen. tephen Townsend, the top U.S. commander in Iraq who heads the war against IS in the Middle East, predicted that Raqqa and Mosul would fall "within the next six months."
But as the 5-month-old battle to drive IS out of Mosul drags on with savage street fighting and waves of IS suicide bombers, it is clear that months of brutal combat lie ahead in both places even though IS is having to fight on several fronts simultaneously.
IS remains cohesive enough to have launched a major offensive against the regime-held sector of the eastern city of Deir ez-Zor, the Assad government's last pocket in the largely desert region southeast of Raqqa and one of the regime's weak spots, on Jan. 15.
By all accounts, the IS push is the group's most important offensive in the region since early 2016, reflecting the jihadists' determination to counter the relentless pressure on their main citadels.
IS has held much of Deir ez- Zor province since 2014. The desert province borders Iraq and has been a key link between IS forces in Raqqa and Mosul. The province also contains Syria's major oil fields, the jihadists' economic backbone during their occupation of the region.
Meanwhile, the U.S.-backed and Kurdish-dominated Syrian Democratic Forces reported advances on Raqqa in an offensive that began on Nov. 5 in large part to stop IS moving reinforcements between the Syrian and Iraqi fronts.
The SDF said it was receiving increased U.S. support as its forces battled to cut the jihadists' last supply routes into Raqqa, including the key road linking it to Deir ez-Zor to the southwest.
The 30,000-man SDF has recaptured territory north and west of the city in the first two phases of the offensive supported by U.S. and French special forces and heavy coalition airstrikes.
One of the main objectives is retaking IS-held town of Tabqa on the Euphrates, 25 miles west of Raqqa. It is near the Thawra dam, the largest in Syria, which supplies much of the country's electrical power and is crucial for irrigation.
"Given Raqqa's location on the north bank of the Euphrates, the new offensive could cut the city off from the entirety of ISIS-held territory, not just Deir ez-Zor," observed French analyst Fabrice Balanche of the Washington Institute for Near East policy.
With all bridges spanning the Euphrates between the Iraqi border and eastern Raqqa destroyed, the city "will be surrounded when the SDF reach the Euphrates, with the river acting as a natural barrier trapping ISIS in the city," Balanche noted. "Of course, ISIS fighters could cross the river with boats but they would be easy targets for U.S. aviation and could not carry heavy equipment."
Control of the Euphrates dams, including one at Kadiran, six miles downstream from Thawra, is vital for the forces tightening the noose around Raqqa.
Balanche observed that "fully controlling both dams is still a prerequisite for assaulting Raqqa because of the threat that ISIS might destroy them and unleash a massively destructive flood downstream."
The third and final phase, launched Feb. 4, aims to encircle the city and cut off the road to Deir ez-Zor, where the United Nations estimates more than 90,000 civilians are trapped.
On Feb. 6, regime forces and their militia allies pressed IS's last stronghold in neighboring Aleppo province at al-Bab, a large town 15 miles south of the Turkish border.
The Syrian Army, preceded by helicopters dropping highly destructive barrel bombs, is pushing towards al-Bab from the south while Turkey-backed rebels approach from the north.
On Feb. 23, the Turkish Army claimed to have seized control of most of al-Bab. If true this opens the way for the offensive against Raqqa.
This article orginally appeared at The Arab Weekly.