Terrorism remains a contested term, with no set definition for the concept or broad agreement among academic experts on its usage. Bruce Hoffman of Georgetown University has defined terrorism as “violence—or equally important, the threat of violence—used and directed in pursuit of, or in service of, a political aim”. Similarly, Louise Richardson of Oxford University believes terrorism is “deliberately and violently targeting civilians for political purposes.” Under these definitions, if there is no political aim, it is simply a crime and, if there is no violence, it is not terrorism.

The recent spate of extremist attacks in the United States and Europe have highlighted the difficulty of defining what constitutes “terrorism” and has led to two key questions. First, do these attacks and other forms of extremism constitute terrorist acts? Second, should the groups who incite hatred be held responsible for these attacks and labelled as terrorists even if they don’t directly participate in the violence?

An important distinction is that violent attacks often come from individuals who are inspired by, but not directly a part of, likeminded ideological groups. Therefore, aligning extremist hate groups with the definition of terrorism is more tenuous and difficult compared to the more obvious cases of ISIS, Al-Qaeda and others whose acts of violence are often directly coordinated, commanded and encouraged by their central leadership. In the case of ISIS, this was evident in its acquisition of territory in Iraq and Syria through violent means, its targeting of Shi’a Muslims, Yazidis and Christians in the process, and its direct command of fighters in Iraq and Syria.

However, recent violent acts from individuals are said to have been inspired by extremist hate groups. One such example is Darren Osborne, the Finsbury Park mosque attacker in London, who researched and downloaded material from Britain First, a fascist far-right political organisation. Furthermore, Osborne also had direct Twitter contact with one of Britain First’s leaders. He threatened to “kill all Muslims” and deliberately targeted the Finsbury Park Mosque, murdering one person and injuring 12 others in the attack.

That violent attack was reminiscent of similar acts of extremism from individuals inspired by extreme Islamist propaganda, notably the Westminster Bridge and London Bridge attacks in 2017. Mrs. Justice Cheem-Grubb, who was the judge during the trial of Osborne, labelled his deadly attack as an act of terrorism saying, “This was a terrorist attack. You intended to kill.…”

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