Iraq declared victory in its three-year war against Islamic State last week, after recapturing the last areas still under the militants’ control.
Levitt, who spoke to Newsroom during a visit to New Zealand, said Islamic State’s defeat did not mean it was entirely gone, but would instead change the way it operated.
“It will revert back to an insurgency which is from whence it came, and everybody’s expecting some very difficult times ahead from a domestic security perspective in Iraq.
“This is a group that is very capable as an insurgency: yes, they’ve lost all this territory, yes they’ve lost money, they’ve lost access to taxing large populations and plots of land and they’ve lost controlling land that was resource-rich, but you don’t need a lot of money to carry out an insurgency, and they will do that to great effect.”
He believed Islamic State would be able to expand its insurgency in Syria, where there were “seams between pockets of authority” given the lack of an official regime, while it was continuing efforts in other areas such as the southern Philippines.
Levitt said the organisation would also continue to be a terrorist threat, attempting and occasionally succeeding in carrying out attacks, with an increased threat of “lone wolf” incidents.
“What is new, inspiring people who have never met them, have never travelled to them, have never been in their training camps but are inspired by the messages and narratives online.”
While those sorts of terrorists would usually struggle to carry out a complex attack given their lack of training, recent attacks had shown the effectiveness of other methods.
“Renting a truck is very inexpensive, ramming it into a bunch of people could be a very successful way of carrying out a terrorist attack. In the United States it’s not hard to get your hands on a gun – certainly a semi-automatic, or even an automatic.”
NZ counter-terrorism ‘dominated’ by Islamic State
The GCSB and SIS briefing to the incoming minister released last week said the counter-terrorism environment in New Zealand was still “dominated” by the influence of Islamic State.
“Violent extremist ideology and messaging, primarily accessed through online content and social media platforms, continues to resonate with a small number of individuals in New Zealand,” the briefing said.
While New Zealand’s relative distance meant it had been “sheltered” from attacks, Levitt said it could not be assumed that it was not at risk.
“The bigger issue though is that borders and oceans aren’t what they once were, and homegrown violent extremism is a huge problem, especially in the United States.”
New Zealand’s overseas population was also at risk, he said.
“I travel for work and vacation, and almost everywhere I go I bump into people from New Zealand. It’s like there a lot more of you than there actually are, and certainly in Southeast Asia there are some acute threats and that is something I think is of immediate concern.”
Levitt said the instability caused by Islamic State was part of wider concerns in the Middle East.
He was particularly concerned by the threat still posed by Syrian president Bashar al-Assad, who he described as “the single greatest poster child for radicalisation and recruitment”.
“People in Europe want there to be some type of reconciliation and reconstruction so they can send their refugees back, and I tell them as long as Assad is in power they will never go back, there will never be reconstruction and there will never be reconciliation.”