At this stage, there is no hard evidence. But reports from the US and Britain suggesting Daesh may have caused the Russian plane crash in Egypt are raising the alarm among experts, who say such an act would be a frightening change in tactics by the extremist group.
It would also underscore the failure so far of the US-led coalition to deter the terrorists - despite the recent addition of Russia to the seemingly formidable forces arrayed against them.
Russian and Egyptian officials say any talk about a bomb is premature, and aviation authorities are working on all possible theories as to why the Airbus A321-200 crashed Saturday in Egypt’s chaotic Sinai Peninsula, 23 minutes after takeoff.
Still, British Prime Minister David Cameron said Thursday it was “more likely than not” that an explosive device brought the jetliner down. If that proves to be true, and if Daesh was responsible, it would be the terrorist group’s largest act of transnational terrorism by far.
While Daesh has claimed responsibility for deadly attacks that struck tourists in Tunisia and Shiite mosques in Gulf countries - claims that have not been proven - it has so far refrained from spectacular Al Qaida-style attacks on airliners. It has focused instead on seizing and expanding territory it already holds in Syria and Iraq, and establishing branches in other countries like Egypt and Libya.
And while some attacks in the West may have been inspired by the group, there has been no clear evidence that any of them was planned or directed by the group itself.
“The Sinai attack would be a first, and would signal that Daesh has become both capable of - and interested in - joining the dreadful ranks of global terrorism,” concluded an analysis by the Soufan Group, a private geopolitical risk assessment company.
Given Daesh’s success in creating mayhem in the region through its brutal tactics and ferocious fanaticism, such a metamorphosis would be a major challenge for security services around the world.
Daesh has claimed responsibility for bringing the Russian plane down in written statements, as well as video and audio messages posted on the Internet this week. It said the attack was retaliation for Russia’s air campaign against Daesh- and other groups - in Syria, where Moscow wants to preserve the rule of President Bashar Al Assad. The group warned Putin that they would also target him “at home.”
But Daesh has not offered any details to back its claim. While releasing specifics would add credibility, the group may be withholding either because its claim is false, or because doing so would undermine plans for similar attacks in the future - or because the aura of mystery might deepen its mystique among die-hard followers.
A US official briefed on the matter said that intercepted communications played a role in the tentative conclusion that Daesh’s Sinai affiliate planted an explosive device on the plane.
However, the official added that if it was a bomb, intelligence analysts don’t believe Daesh leaders in Syria ordered the operation, but rather that it was planned and executed by the group’s Sinai affiliate, which operates autonomously.
Daesh’s insistent series of responsibility claims suggests it is trying to boost its global credentials.
Until now, the main advantage it has claimed over Al Qaida is its hold over a significant chunk of territory in Iraq and Syria.
Ayman Al Tamimi, an expert on rebel and Islamist extremist groups and a fellow at the Middle East Forum think tank, said bombing a jetliner becomes a significant “one-up” in the rivalry with Al Qaida.
“If Daesh is capable of conducting attacks like this - particularly against a target now widely reviled (Russia) - this could bolster their appeal in the militant world,” he said.
If a bomb brought down the plane, it would not be the first time a Russian jetliner was targeted by Islamist militants. Two suicide attackers brought down two Russian planes over Russia in 2004, killing 89 people - attacks claimed by Chechen rebels. Chechens and other militants from the northern Caucasus still have lots of reason to strike at Russian targets.