Members of Iraqi police forces celebrate on a street on June 27, 2016 in western Fallujah, after Iraqi forces retook the embattled city from the Islamic State.HAIDAR MOHAMMED ALI/AFP / Getty Images
Iraq's army succeeded this week in liberating the city of Fallujah from the extremist fighters of the Islamic State movement who first occupied the provincial centre just west of Baghdad more than two years ago.
And, as the national flag was hoisted over the city's mostly empty buildings, Iraqi Prime Minister Haider al-Abadi vowed that soon the flag will fly in Mosul as well, a reference to Iraq's much larger northern city that serves now as the capital of Islamic State's so-called caliphate.
But while the news from Fallujah was promising to those who seek Islamic State's demise, as was news from Syria where U.S.-led efforts to defeat IS forces have made gains in the area of Aleppo, no one should think Islamic State is on the run.
The battle for Mosul, like the battle for Raqqa, where IS commanders are headquartered in Syria, is still far off. And even if IS forces are vanquished from these cities, the Islamic State movement is not about to vanish.
"The 'state' in Islamic State will collapse," says the Beirut-based analyst Rami Khouri, "but IS will not disappear."
Already the IS movement has followers from Southeast Asia to North and Central Africa and Mr. Khouri foresees a more dispersed group of extremists carrying on long after any fall of Mosul.
Evidence of this could be seen earlier this month in Orlando where Omar Mateen rounded up and killed 49 people in a gay bar and told 911 he was acting in the name of Islamic State, and in the Philippines where Canadian traveller Robert Hall was beheaded by a group of rebel kidnappers known as Abu Sayyaf that long ago adopted the flag and mantra of the IS movement.
What matters to Islamic State, Mr. Khouri recently wrote, isn't necessarily territory. "What matters to IS and will allow it to persist for some time is the shared mindset of a large number of people around the world – from hundreds of thousands to perhaps a few million – who have lost confidence in their existing political, religious and socio-economic institutions."
Islamic State, he says, can morph into a diverse group of followers "who operate in a highly personalized and decentralized manner around the world."
Some argue, however, that without territory, Islamic State cannot exist as a caliphate, which is one of the things that sets it apart from al-Qaeda, its great rival. And without a caliphate, the flow of disciples joining the cause may well dwindle.
To write off the Islamic State movement this way is to miss an important point, says Emmanuel Sivan, professor emeritus at Hebrew University in Jerusalem. Despite its name and the trappings of Islamic Salafism, Islamic State is not particularly Islamic, he argues.
It's all "hogwash" intended to entice followers with the romantic notion of re-establishing an Islamic order based on the seventh-century designs of the Prophet Mohammed, Prof. Sivan said in an interview.
This group, he noted, was created by a collection of disgruntled Iraqi Sunnis in the wake of the U.S.-led invasion of Iraq in 2003. Known at first as al-Qaeda of Iraq (AQI), the group was determined to rid Iraq of its U.S. occupiers and to restore Sunnis to a place of prominence in the country. They had ruled the roost under Saddam Hussein and were being ostracized, even driven from their homes, by the ruling Shia majority.
Forced underground in 2007, AQI would emerge as Islamic State of Iraq, later Islamic State.
Even though a defeat in Mosul would deny the organization its territorial base of operations, it will not deprive the group of its raison d'être. "As long as they are ruled by Shiites, they will continue to fight," he argues.
And even defeat in Mosul is not a foregone conclusion.
IS forces have had two years to build up the defences of this city – Iraq's third most populous after Baghdad and Basra – and it's unclear just who will carry the fight to them.
The U.S.-led air coalition will not bomb the historic and still heavily populated centre. The Iraqi army lacks sufficient numbers of well-trained special forces and the Shia government, pressured by the United States, says it will not allow the effective Iranian-backed Shia militias to enter the historically Sunni city.
Nearby Kurds, who have historic ties to the city, have cut off roads leading in and out of Mosul from the west, north and east. But these peshmerga fighters lack the numbers to take the city by themselves, and the Iraqi government doesn't want them threatening the Arab population.
In the end, there could well be a stalemate, noted Graeme Wood, a contributing editor to Atlantic Magazine, in an extensive article last year.
The only thing Islamic State might lose, Mr. Wood suggested, would be its caliphate veneer.