Movements like the self-proclaimed Islamic State must innovate or die. An insurgency is always weaker than the government or governments it faces, so it must make the most of its limited resources and whatever advantages it does enjoy. Often what it has in its favor is a lack of restraint and a willingness to carefully orchestrate violence to maximize its effects. That is why groups like the Islamic State rely on terrorism, using it to generate fear disproportionate to the resources it takes to execute an attack. In strategic terms, terrorism is cheap but potentially effective, particularly if the victim overreacts.
But like all terrorism-based movements, the Islamic State faces a persistent dilemma: Over time, the ability of any specific form of terrorism to produce fear declines as potential targets mentally adjust. The first few instances of some horrific type of attack—a suicide bomb in a crowded market, for instance—produce extensive psychological effects, but the 20th, 50th or 100th time less so. This means that terrorist groups must constantly seek new forms of attacks to produce the fear they seek.
This is where the Islamic State finds itself today. Horrific, well-publicized brutality against perceived enemies in Syria and Iraq promoted it from the “junior varsity” of violent Islamic extremists to the top tier. Once that happened, the group found that orchestrating or inspiring murder sprees in Europe, the United States and elsewhere elevated it even further, perversely augmenting its standing among violent, angry, alienated and, in many cases, mentally unbalanced Muslims around the world. But now it must up the ante again, finding new ways to create the fear it needs to fuel its strategy. Hence the Islamic State is innovating, looking for “the next big thing” in terrorism.