LONDON — In the weeks after Islamic State operatives struck Paris in November 2015, the group released a prerecorded video of the killers. They stared into the camera, waved serrated knives, raged at the West, and warned Britain: You’re next. Footage showed scenes of London Bridge through a gunsight.
For the next 13 months, the Islamic State and those inspired by them killed and maimed in Brussels, Berlin, Nice, Normandy, and across the Atlantic in California and in Florida.
Yet the rhetoric against Britain began to feel like the frothy threats made by the group toward other countries that had avoided attacks, including Iran: loud and menacing but ultimately empty.
Until now. The strikes in the past week against London and Tehran followed back-to-back attacks, by an assailant who used an SUV to smash into pedestrians on Westminster Bridge in March and a suicide bomber at a pop concert in Manchester in May. “This is for Allah!’’ the attackers were heard screaming in the latest bloodshed in London as they plunged knives into their victims.
British police said Saturday they had arrested two more suspects over the London Bridge attack, and revealed that the carnage could have been worse had the attackers succeeded in their goal of renting a truck, rather than a van, to mow down pedestrians, the Associated Press reported.
From a publicity standpoint, the attacks in Britain and Iran are a lift to the Islamic State as it loses ground steadily in Syria, Iraq, and Libya.
Some analysts have interpreted the strikes as a bid by the group to demonstrate its resilience, even as its territory-holding caliphate slowly disappears.
But a review of court records and statements by officials suggests that the violence in London and Tehran was more than just a message.
It reflected persistent efforts by the Islamic State since its rise in 2014 to hit targets once thought unassailable — especially in Britain. During this period, officials in the United Kingdom intercepted and foiled more than a dozen plots — including five just in the past three months.
The number of disrupted plots appears to be far greater in Iran, a Shi’ite-majority country loathed by the militant Sunni extremists of the Islamic State, which has aimed to hit Iran since at least 2007.
A day after the deadly assault last week on the Parliament building and the tomb of Iran’s revolutionary founder, Iranian intelligence officials said they had thwarted 100 terrorist plots in the past two years.
Hours after the violence in Iran, the Islamic State released its glossy, online magazine, directly challenging skeptics who have questioned the group’s stamina as its territory shrinks.
“What many of these analysts failed to admit, however, is that losing territory was nothing new for the Islamic State,’’ the article said, referring to the group’s near-defeat in 2011 at the hands of US forces in Iraq.
“The reality faced by the Crusaders today is that despite their claims that the Islamic State has been weakened,’’ it said, “strikes in the heart of the Crusaders’ strongholds in the West will continue to occur just as suddenly and unexpectedly.’’
While little detail has been shared with the public about thwarted attacks in Iran, plots neutralized in Britain show how the Islamic State’s reach grew with each attempt. The techniques used by the frustrated attackers, the types of targets they chose, and the kind of coaching they received broadly follows the arc of the group’s evolution as it repeatedly struck elsewhere in Europe.
The earliest instances involved would-be attackers who had ideological affinity for the Islamic State but no direct communication with ISIS.
They took their direction from the many YouTube videos they had watched showing Islamic State atrocities, and from detailed instructions delivered online by Abu Muhammad al-Adnani, the group’s spokesman before he was killed in August 2016.
