Confronting ‘non-violent extremism’ has become a priority for policy makers in both Western and Muslim-majority countries. But the term has also been politically controversial, with suggestions that it is inherently discriminatory, and polices thought and free speech. This paper explores the development of the concept of ‘non-violent extremism’ within a policy context, drawing particularly on the example of the UK; it uses data-driven research to explore the complex relationship between violent and non-violent extremism; and explores the implications of this understanding for efforts to respond to extremist violence. This paper largely focuses on the debate around Islamist extremism, but also has implications for other forms of ideological extremism which have both a violent and non-violent component, including the Far Right.

After the 9/11 attacks shook the world and demonstrated the potential destructive power and global reach of violent extremism, huge investment was made in an international programme of counter terrorism measures, in an effort to safeguard populations against non-state actors determined to pursue indiscriminate violence for political ends.

However, one of the major developments in the last decade has been the increase in efforts to counter extremism, with interventions that operate increasingly upstream, focusing on addressing the conditions, vulnerabilities and mindset that might make a person resort to extremist violence, rather than simply preventing the violence itself. A growing part of this policy shift has been an emphasis on tackling so-called ‘non-violent extremism’, and attempts to address the kinds of ideologies that are perceived to legitimise and drive terrorism ‘upstream,’ before they manifest violently.