Testifying before the House Homeland Security Committee, Thomas Joscelyn argued that the recent string of battlefield victories against Islamic State (IS) does not mean the organization is on the brink of collapse. He pointed to IS’s successful rebound from near-defeat in the years between 2011 and 2014, its international infrastructure, and the fact that U.S. intelligence has repeatedly underestimated the strength of its forces:
Since November 2014, when the self-styled caliph Abu Bakr al-Baghdadi first announced the establishment of “provinces” around the globe, Islamic State’s membership grew outside of Iraq and Syria. This further complicates any effort to estimate its overall size. Some of these “provinces” were nothing more than small terror networks, while others evolved into capable insurgency organizations in their own right. . . . Although it is impossible to judge the extent of Islamic State’s cohesion, as much of the data is not available, there is at least some connectivity between the group’s leadership and its “provinces” elsewhere. . . .
While their fortunes may rise or fall at any given time, this global network of Islamic State “provinces” will remain a formidable problem for the foreseeable future. Not only are they capable of killing large numbers of people in the countries they operate in, this structure also makes tracking international terrorist travel more difficult. For instance, counterterrorism officials have tied plots in Europe to operatives in Libya. This indicates that some of IS’s “external plotters,” who are responsible for targeting the West, are not stationed in Iraq and Syria. The U.S.-led air campaign has disrupted the Islamic State’s “external operations” capacity by killing a number of jihadists in this wing of the organization. But others live.
The cult of martyrdom has grown. A disturbingly large number of people are willing to kill themselves for Islamic State’s cause. The number of suicide bombings claimed by the so-called caliphate dwarfs all other jihadist groups, including al-Qaeda. . . .
There are [also] legitimate concerns about the possibility of well-trained fighters leaving Iraq and Syria for the West now that IS is losing its grip on some of its most important locales; . . . the threat posed by these returnees . . . is just one part of the overall picture.