The Iraqi government has declared victory over ISIS, and US President Donald Trump has taken credit for the ISIS caliphate's collapse, NBC News reported.
"ISIS is now giving up, they are giving up, there are raising their hands, they are walking off. Nobody has ever seen that before," Trump said.
But experts both in and outside the US government warn that ISIS remains a lethal force, as shown by a double suicide bombing in Baghdad Monday that killed 100. As the caliphate has collapsed the number of active terrorists in Syria and Iraq may have dropped below 3,000, there are many more ISIS loyalists still on the scene.
Hassan Hassan, the coauthor of the book "ISIS: Inside the Army of Terror," estimates that some 7,000 ISIS-loyalists remain.
"They operate as a terrorist and insurgent organization almost purely now, versus as a conventional fighting unit," said Hassan, a senior fellow at the Tahrir Institute for Middle East Policy. "There are still so many in Syria, in the Abu Kamal and Deir al-Zour areas. A lot of them are Iraqis who fled across the border."
Hisham al-Hashimi, an adviser to the Iraqi government in its battle against ISIS, said that while the number of active terrorists on the battlefield is probably in the range of 1,000 to 1,500, the actual number of ISIS-loyalists in Iraq and Syria is closer to 10,000.
Since airstrikes in Iraq and Syria began in 2014, a territory that was once the size of Ohio has been almost entirely recaptured by US-led coalition-backed forces.
The terror group's two biggest strongholds, Mosul in Iraq and its de facto capital of Raqqa in Syria fell in July and October respectively to coalition-backed forces.
Trump has given significant leeway to the Department of Defense to carry out its mission and help local ground forces recaptured the remaining territory.
Trump pointed to his leadership as one of the key factors driving ISIS terrorists off the battlefield.
"I totally changed rules of engagement. I totally changed our military, I totally changed the attitudes of the military and they have done a fantastic job," Trump said.
ISIS has not only lost territory, but it is being denied access to revenue sources such as oil and gas and cash reserves that once amounted to more than $1 billion in 2014.
ISIS had also generated some $30 million per month in Iraq from taxation and extortion in 2015, according to Iraqi and US government estimates.
"There is a big difference between defeating them militarily on the battlefield and eliminating ISIS as a terrorist organization," said Daniel Glasser, the Treasury Department's assistant secretary for terrorist financing under US former President Barack Obama.
Defense Secretary Jim Mattis said in December that US-backed forces were in the process of "crushing the life" out of ISIS.
"We told you that the [ISIS] caliphate was going to go down," Mattis added, and "as we sit here today at the end of 2017, the caliphate is on the run, we're breaking them."
But he also said the "war is not over." Mattis emphasized that much work remained to prevent the emergence of what the retired four-star general called "ISIS 2.0," noting that the group may attempt to return to its modest, low-budget terror roots in an effort to once again exploit sectarian rifts in Iraq and Syria.
On Friday, the Pentagon released a National Defense Strategy that said terrorism remained "a persistent condition ... despite the defeat of ISIS's physical caliphate."
A day earlier, Secretary of State Rex Tillerson, laying out the Trump administration's broad strategy for Syria, said a quick withdrawal from Syria would give the terrorist group an opportunity to make a comeback.
"The United States will maintain a military presence in Syria focused on ensuring (ISIS) cannot re-emerge," he said. "We cannot make the same mistakes that were made in 2011 when a premature departure from Iraq allowed al-Qaeda in Iraq to survive and eventually morph into (ISIS)."
This week's suicide bombing in one of Baghdad's busiest public squares rattled the city's growing sense of security. And while ISIS is no longer earning millions from oil and extortion, it has reverted to raising funds from charities and wealthy donors.
The US estimates of the terror group's remaining strength, meanwhile, are similar to those offered by outside experts. Like Hassan and al-Hashimi's figures, recent US public estimates of active ISIS terrorists have ranged from 3,000 to 1,000, with the number falling rapidly.
On background, US officials say they estimate ISIS non-battlefield strength in Iraq and Syria at 6,000 to 8,000, in line with Hassan's figure but lower than al-Hashimi's of 10,000, which includes potential lone-wolf attackers.
ISIS is "transforming into a new threat," said Glasser, who is now a principal at the Financial Integrity Network. "They don't have this safe haven and it makes it harder for them to plan catastrophic attacks on us, but at the same time the threat is very much still there, and more diffuse and a little bit less predictable."