European States’ Obligations to Repatriate the Children Detained in Camps in Northeast Syria in combating terrorism371 and undermines States’ ability to fulfill their obligation to investigate and prosecute international crimes and/or terrorist offenses.372 Applying these standards to the situation of European children detained in northern Syria, it can be said that European States’ obligation to admit or readmit their nationals detained in Syria in fulfillment of a right to return under international human rights law also serves to fulfill their obligations under international counter-terrorism laws, as well as their “international obligation derived from the international regulation of responsibilities between the state of origin and state of residence, and between personal sovereignty and territorial sovereignty.”373 Therefore, European States “must not undermine the principle of reciprocity or commitments to international cooperation, by stripping a person of nationality, expelling a person to a third country or subjecting a person to removal proceedings, thereby exporting the stated security risk to a third country and failing to take responsibility for their own nationals.”374 iii. International Refugee Law Finally, some argue that the foreign children detained in northern Syria meet the requirements for refugee status “because they are being persecuted as a particular social group, which is defined as children who lived in the ISIS regime and who do not have the ability to be repatriated to their home country.”375 Under international refugee law, the right of refugees to return to their country of origin is fully recognized. 376 In this regard, while the nonrefoulement principle protects refugees against forced return, the right-toreturn principle allows refugees to be voluntarily repatriated. 377 While an 371 UNSC, “Resolution 2178 (2014) on Threats to International Peace and Security Caused by Foreign Terrorist Fighters”, S/RES/2178 (2014), 24 September 2014, para. 11-14. UNSC, “Twenty-Third Report of the Analytical Support and Sanctions Monitoring Team Submitted Pursuant to Resolution 2368 (2017) Concerning ISIL (Da’esh), Al-Qaida and Associated Individuals and Entities,” S/2019/50, 15 January 2019, para. 93. 372 PACE, “Withdrawing Nationality as a Measure to Combat Terrorism: A Human-Rights Compatible Approach?”, Resolution 2263 (2019), para. 8. 373 Kay Hailbronner, “Readmission Agreements and the Obligation on States under Public International Law to Readmit their Own and Foreign Nationals”, 1997, p. 4. 374 OSJI/ISI, “Principles on Deprivation of Nationality as a Security Measure,” 2020, Principle 11.2. 375 Ana Luquerna, “The Children of ISIS: Statelessness and Eligibility for Asylum under International Law,” 2020, pp. 178-190. 376 UNHCR, “Handbook on Voluntary Repatriation: International Protection,” 1996, Subsection 2.1. 377 See: UNHCR, “The International Law of Voluntary Repatriation,” pp. 1-2; UNHCR, “Handbook on Voluntary Repatriation: International Protection,” 1996. Note the emphasis on: “[r]epatriation of women and children detained in the camps in northern Syria, must not come at the cost of violating the principle of non-refoulement. Member States are obliged not to expel, return, extradite or otherwise remove a person to another State, when there are substantial grounds for believing that they would be at risk of being subjected to serious violations of human rights, including torture or cruel, inhuman and degrading 65