of support for a leader of a “terrorist organization”, per se, have not justified interference in past cases.205 Moreover, if restrictions are to be justified based on threats to national security, the threat cannot be abstract or hypothetical, but must involve at least a reasonable risk of serious disturbance. Restrictions on freedom of expression must be exceptional, strictly justified as necessary and proportionate by reference to all the circumstances of the individual case. Restrictions cannot be justified on the basis that the ideas and opinions are not popular, are disfavoured or considered to represent an abstract danger. Alternative Narratives by Credible Messengers The UN Secretary General’s Plan of Action on Preventing Violent Extremism emphasizes the importance of fostering and creating platforms for dialogue and discussion. It notes that it is important “to promote tolerance and understanding between communities, and voice their rejection of violent doctrines by emphasizing the peaceful and humanitarian values inherent in their theologies”.206 It also makes clear that it is important to “promote, in partnership with civil society and communities, a discourse that addresses the drivers of violent extremism, including ongoing human rights violations.”207 Initiatives that focus on fostering debate and engaging in discourse are undermined in contexts in which freedom of expression is unduly suppressed in the name of countering terrorism. If the debate is to be taken seriously, it must enable the expression of a range of opinions, including offensive and even anti-democratic speech, and embrace not only the expression of views that the state or the majority of society endorse but also those that they do not. A holistic, long-term and human rights-compliant approach to prevention would safeguard freedom of expression, subject to the acceptable limits provided by international law, including concerning the prohibition of incitement to ­terrorist violence. States have increasingly engaged in measures directed at fostering “alternative narratives” to the ideology advanced by groups such as ISIL. The credibility and effect of such initiatives depends on who they are delivered by and whether initiatives genuinely open the debate, rather than gearing it only towards “acceptable” narratives. Emerging research suggests that when the primary motivation for returning FTFs is disaffection with the groups they joined abroad, they may constitute effective advocates to dissuade prospective recruits. Successful reintegration and rehabilitation, as set out below, may 205  Yalçinkaya and Others v. Turkey, ECtHR, Judgment of 24 June 2014 (French), para. 34. The UN Human Rights Committee, in its General Comment on Article 19, stressed with reference to concerns expressed in concluding observations on the United Kingdom and Russia that offences such as “encouragement of terrorism” and “extremist activity” as well as offences of “praising”, “glorifying”, or “justifying” need to be based on clearly defined law to ensure that they do not lead to unnecessary or disproportionate interference with freedom of expression. See: General Comment No. 34, CCPR, para. 46, op. cit., note 197. 206  “Plan of Action to Prevent Violent Extremism: Report of the Secretary-General”, UN Secretary General, UN Doc. A/70/674, 24 December 2015, para. 49 (e), <www.un.org/en/ga/search/view_doc.asp?symbol=A/70/67>, (hereafter, UNSG Plan of Action on PVE). 207  Ibid., para. 51 (g) Rec 3(7). The paragraph goes on to recommend that states “Address any existing human rights violations, as a matter of both legal obligation and credibility”. Guidelines for Addressing the Threats and Challenges of “Foreign Terrorist Fighters” 57