72 QIL 60 (2019) 69-97 ZOOM IN (2014) asks States to criminalize also preparatory acts, a controversial obligation that undermines traditional legal principles such as legal certainty, and passive conducts such as being recruited by a terrorist group and receiving terrorist training.12 As a result even individuals − in most instances women and children − who might have been recruited and trained by ISIS, but did not perform combat functions and/or were not directly involved in terrorist activities risk being swiftly labelled as FTFs. Given the current lack of agreement on the exact meaning of ‘terrorism’ as a legal concept,13 the definition of FTFs provided in Resolution 2178 (2014) does not offer sufficient guidance to the Member States called to determine whom, exactly, falls within this category. Due to the fact that it is extremely difficult to ascertain whether an individual has committed terrorist offences while in Syria or Iraq, States usually base their initial assessment on the ‘affiliation’ with groups labelled as ‘terrorist’;14 with 22 States in the EU − and many more around the world − criminalizing tout court the membership, participation in or leadership of a terrorist group,15 or even trying to enter a given territory of a foreign country where certain terrorist groups are active.16 Therefore, foreigners with ties to ISIS will be − virtually in every case and under every domestic jurisdiction – prosecuted as FTFs and not merely regarded as foreign nations-security-council-urges-states-to-combat-foreign-terrorist-fighters-but-does-notdefine-terrorism/>; F Capone, ‘Countering “Foreign Terrorist Fighters”: A Critical Appraisal of the Framework Established by the UN Security Council Resolutions’ (2016) 25 Italian YB Intl L 227. 12 L van der Heide, ‘Preventing Terrorism in the Courtroom – The Criminalisation of Preparatory Acts of Terrorism in the Netherlands’ (2015) 26 Security and Human Rights 162, 163-164. 13 Capone (n 11) 237-242. 14 Ambos, ‘Our Terrorists, your Terrorists?’ (n 11). 15 B van Ginkel, E Entenmann, ‘The Foreign Fighters Phenomenon in the European Union Profiles, Threats and Policies’ ICCT (April 2016) 6 <www.icct.nl/wpcontent/uploads/2016/03/ICCT-Report_Foreign-Fighters-Phenomenon-in-the-EU_1April-2016_including-AnnexesLinks.pdf>. 16 For example, the Australian Counter-Terrorism Legislation Amendment (Foreign Fighters) Act 2014 makes it an offence to enter a ‘declared’ area without a legitimate purpose. According to division 119 the Minister for Foreign Affairs may declare such an area in a foreign country when a listed terrorist organization is engaging in a ‘hostile activity’ on that territory. ‘Analysis and Recommendations with regard to the Global Threat from Foreign Terrorist Fighters’, UN Doc S/2015/358 (19 May 2015) para 54. Similarly, France has broadly criminalized ‘having been abroad in a theatre of operations of terrorist groups’, see van Ginkel, Entenmann (n 15) 32.