US President Donald Trump recently declared that the Islamic State (ISIS) has successfully been defeated. However, the group continues to demonstrate that it still has some fight left.

"We've defeated ISIS," Trump stated in a recent interview with The Associated Press. "ISIS is defeated in all areas that we fought ISIS, and that would have never happened under President Obama."

The US military has not used such definitive terms. US military officials invariably point out that while the United States and its partnered forces in Iraq and Syria have destroyed ISIS's physical caliphate, declared following Mosul's capture in June 2014, the group is still fighting and, as predicted, reverting to its roots as a deadly non-state actor and terrorist organisation.

Trump extolling the numerous battlefield defeats afflicted on ISIS since he took office is understandable. After all, the group's vicious terrorist attacks on Western countries have been hugely reduced and its threats ring far more hollow than they did just over a year ago. Nevertheless, the threat ISIS still poses should not be dismissed or underestimated.

In January 2014, President Obama argued that ISIS was little more than a junior varsity basketball team compared to Al-Qaeda.

"The analogy we use around here sometimes, and I think is accurate, is if a JV team puts on Lakers uniforms, that doesn't make them Kobe Bryant," Obama told The New Yorker at the time.

That same month ISIS seized the Iraqi city of Fallujah and within six months had conquered vast swathes of Iraq and Syria upon which it established a terror state the size of the United Kingdom, making Obama's comment look very frivolous in retrospect.

Trump could fall into the same trap by prematurely declaring victory over the movement, especially if he actually begins acting in accordance with that misguided belief.

Former Iraqi Prime Minister Haider al-Abadi also prematurely declared a "final victory" over ISIS in December 2017. While Baghdad successfully recaptured Mosul in July 2017 and reclaimed the vast majority of territory the group carved from Iraq ISIS has demonstrated that it still poses a significant threat.

Since Abadi's declaration, the Iraqi military has launched large-scale operations against ISIS remnants in the country.

In July Baghdad launched its 'Revenge of the Martyrs' operation targeting the group in rural areas between Baghdad and Kirkuk. This October the Iraqi military launched a large operation in Diyala province which targeted an estimated 40 ISIS positions.

ISIS still poses a significant threat to Iraq. The group is believed to have behind the car bomb attack on the town of Qayyarah, south of Mosul, that killed three and injured 20 on October 23. 

Just one day before the Kurdistan Region Security Council (KRSC) warned of the continuous threat ISIS poses to both Kirkuk and Mosul.

"During September, unrest increased in Kirkuk and Mosul, among other areas," the KRSC reported on its Twitter account.

"ISIS attacks increased, sometimes targeting multiple villages at once; IEDs [improvised explosive devices] continued on a regular basis, and hits on ISF/PMF homes and figures, and electricity infrastructure have become a feature," it added, referring to the Iraqi Security Forces and the Iraqi state-sanctioned Popular Mobilization Forces paramilitaries by their respective acronyms.

Also according to the KRSC in September the Islamic State, along with "unknown fighters,” were responsible for "at least 22 attacks; more than 25 IEDs targeted Iraqi security forces and civilians, and 9 kidnapping incidents and 5 grenade attacks."

More generally over the past year ISIS has mounted a vicious campaign of murdering village elders, mukhtars, to "completely erode the faith of the population in the security forces" and retain a foothold in Iraq's rural areas, Iraq analyst Michael Knights told The Atlantic magazine last August.

"You can say that almost all of Iraq has been liberated from ISIS during the day, but you can't say that at night," Knights explained.

Also, through its aggressive takeover of Kirkuk in October 2017 Baghdad unwittingly gave ISIS some breathing room. The group has, among other things, exploited the gaps between ISF and Peshmerga lines and capitalized on the mistrust those events created between Baghdad and Erbil.

In neighbouring Syria, ISIS has also demonstrated it still has some fight left in it. On September 10, the US-backed Kurdish-led Syrian Democratic Forces (SDF) began a campaign to wipe the group out in its last redoubts in the country's eastern Deir ez-Zor province. While they are backed by US-led air power, along with American and French ground forces equipped with artillery, ISIS has strongly resisted their advances, particularly in the town of Hajin.

At least 227 SDF fighters have been killed by the entrenched group, which lost 414 of its own. On October 16, Redur Khalil, a top SDF commander, said their offensive will take "much longer than expected" as a result of the tough fight the ISIS remnants are putting up coupled with poor weather.

There are an estimated 3,000 members fighting to retain control.

ISIS exploited a sandstorm that cloaked the region from October 8-15, which made it difficult for supporting aircraft to locate and bomb the group's positions, to counterattack and kill scores of SDF forces and even steal at least one of their US-supplied mine-resistant ambush protected (MRAP) vehicles.

Even when ISIS inevitably loses control of Hajin and the other parts of Deir ez-Zor over which its black flag currently flies, it will likely prove capable of carrying out devastating terrorist attacks as a non-state actor, which is what it's once again doing in Iraq.

Combating this threat could take many years. Consequently, the US and its other counter-ISIS partners need to prepare for a prolonged counter-insurgency campaign and not lull themselves into a false sense of security by prematurely declaring the defeat of this infamous group.