Viewing the threat in a binary fashion — existential or not existential— also fails to account for its dangerous and predictable adaptations over time. The Islamic State has adapted quickly by leveraging havens, especially in cities, and inspiring sympathetic networks throughout the world to present new threats. It reportedly downed a Russian commercial airliner, targeted the Egyptian navy and launched coordinated attacks under the noses of Western security services.

It is flirting with weapons of mass destruction — using chemical weapons, operating a chemical weapons unit and accessing labs at Mosul University. It has used the cyber domain to radicalize using peer-to-peer technologies and to attack online with a new “United Cyber Caliphate.” The siren song of the so-called caliphate has animated a new generation of extremists, including more women. These adaptations will surely present serious threats in the future.

Further, articulating the threat only in “existential” terms leads to a myopic, insular foreign policy. The Islamic State poses a direct threat to U.S. allies, having a deeper impact on those societies — from genocide and displacement of millions of refugees to the radicalization of Muslim youth and the hardening of reactionary forces. The French president has declared repeatedly that Europe is at war, while mourning yet another attack on French citizens; Kurds and Iraqis are defending their families and communities; Jordan, Turkey and Lebanon endure attacks and the massive weight of refugees. To our friends fighting for their survival with the Islamic State on their doorstep, this threat looks existential.