Directed or inspired: What is ISIS's role in the Manchester attack and others like it?
The brother of Salman Abedi, the suicide bomber, claimed they both belonged to the extremist group
The deadly Manchester suicide bombing and its possible connection to ISIS raises questions about the group's direct or indirect role in this attack, as well as others made against Western targets.
The Islamic State in Syria and Iraq is somewhat particular in its claims of responsibility for attacks. It never, for example, took credit for the attack in Stockholm this year, when the driver of a truck plowed into a crowd, killing five.
Nor did ISIS take credit for the New York and New Jersey bombings in September 2016. Yet that same weekend, they took responsibility after a man stabbed nine people in a Minnesota mall.
"They don't claim everything, even those attacks that seem to have a level of inspiration from them," said counterterrorism expert Thomas Joscelyn, who is also senior editor of the Long War Journal.
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But shortly after this week's suicide blast that killed 22 people at the arena where Ariana Grande had just performed, ISIS released a statement claiming responsibility.
"One of the soldiers of the caliphate," it claimed, "placed explosive devices in a gathering of crusaders in the middle of the British city of Manchester."
Authorities have made a series of arrests, including the apprehension of the suicide bomber's brother. Libya's Special Deterrent anti-terror force said in statement that the brother claimed they both belonged to ISIS.
While the level of ISIS's involvement continues to be investigated, CNN reported that the bomber, Salman Abedi, likely received some Islamic State training by travelling to Syria in the months before the attack.
Part of a network
"It's looking more like, at least, he was part of a network that had connections to ISIS in Manchester and Libya," said Alexander Meleagrou-Hitchens, research director of the Program on Extremism at George Washington University.
Abedi is believed to have very recently been in Libya and Syria, returning to Manchester just before the attack.
As well, the level of sophistication of the bomb itself, described by the New York Times as "an improvised device made with forethought and care" suggests a network of individuals were involved, experts say.
"You just don't build a bomb, fill it with shrapnel, and go and kill 22 people," said Aki Peritz, a former CIA counterterrorism analyst. "Somebody needs to show you how to do this."
Abedi seems to be a different case than someone sitting in their grandmother's basement, downloading Jihadi propaganda, who is then inspired to go on a random attack, Joscelyn said.
"As the evidence continues to come in, I do suspect we are going to find a network in the play here," he said.
In their statement, ISIS referred to the bomber as a "soldier," a description usually reserved for those perpetrators who have been inspired, rather than directed, by the group, Meleagrou-Hitchens said.
Omar Mateen, the gunman responsible for killing 49 people at an Orlando, Fla., nightclub last June, had pledged allegiance to ISIS, telling a 911 operator he was an "Islamic soldier." But no evidence surfaced that the group had any role in training or specifically directing his actions.
Yet even if the Manchester bomber was just inspired by ISIS, he was still a product of a concerted effort of the group to get people to commit these types of acts, Meleagrou-Hitchens said.
'Without having a direct hand'
"It is part of the ISIS strategy to inspire people to commit attacks in its name without having a direct hand," he said. "Even though they haven't had a direct hand, they see it as part of their strategy of attacking the West.
"Without their lending legitimacy to this type of activity, these people may not have done this."
Joscelyn also pointed out there are a number of cases in which people are suspected of just being inspired, "but the story turns out to be much more complicated."
He cited some of the smaller-scale knife attacks in Europe in 2016. Initially believed to be only inspired by ISIS, "it turned out that those people, in fact, had received guidance online," Joscelyn said.
He referred to these incidents as "remote-controlled" attacks, in which a handler in Iraq or Syria reaches out to a would-be recruit online and "guides them through their day of terror."
"So that's sort of an innovation that ISIS has taken to a whole new level," he said.
There have also been cases of ISIS-directed attacks, which are usually much larger in scope, more co-ordinated and more devastating. Those include the November 2015 attacks in Paris and March 2016 bombings in Brussels.
The ambiguity around ISIS also makes it difficult to attribute their levels of responsibility for attacks, Peritz said.
"What is ISIS anyway? Is it the philosophy of ISIS? Is it the nation-state of ISIS? Or is it this free-flowing anger in cyberspace that is chock full of grievances toward the West?
"Every time some person commits some atrocity somewhere and claims it's ISIS, is it really ISIS? The answer is we don't know."