#1 up, most likely with only a limited ability to prosecute low-rank ISIS members. There are currently two main options that are being considered by the seven “most affected” countries (France, Germany, UK, Belgium, Netherlands, Denmark and Sweden). First, the option of trials in Iraq, by Iraqi courts, has long been favoured by the French government.70 As a sovereign country, with a functioning justice system, Iraq could possibly prosecute European fighters. In fact, more than 20 Europeans have already been convicted in Iraq. Several challenges stand in the way of generalizing such option, however. Leaving aside concerns about the ability of Iraqi courts to conduct fair trials or their ability to gather evidence against individuals whose crimes might have been limited to the Syrian jurisdiction, the transfer of European fighters from Syria to Iraq (since 95 percent of the European adults are currently detained in Syria) would be deemed illegal according to international law, and ethically problematic since Iraq still practices death penalty. Second, the option of trials in Syria by the Kurdish autonomous administration seems to be gathering increasing support from some governments, notably Sweden and the UK.71 This option would fit better with the argument of “prosecution where the crimes were committed”. The problem is, however, that the Kurdish autonomous administration is not a recognised legal entity internationally, raising serious questions about its legal right to prosecute European fighters (and the status of such judiciary decisions) as well as its ability to conduct such trials. Furthermore, a European support to such initiative would inevitably be interpreted as a form of political support to the Kurdish administration, which could further complicate relations with Turkey and Syria. Either options have clear limitations, but they offer nonetheless viable alternatives to repatriation. They also have in common that European fighters would not only be judged in the region, but also detained there for years to come. This conveniently puts the issue off for governments in the short term, leaving it to their successors. However, it will not make the problem disappear. During their detention period, in Syria or Iraq, European fighters will continue to be at risk of further radicalisation and networking with other foreign ISIS inmates. It should be kept in mind that ISIS was partly a creation of the US clandestine prisons in Iraq (Abu Ghraib and Camp Bucca, notably). While many people beware of radicalisation in Europe’s prisons, it is hard to imagine a worse environment than prisons in Syria and Iraq, where some of the most dangerous terrorists in the world are packed together. Next, there is always the risk of prison breaks, which is unlikely to disappear in the unstable regional environment, with civil unrest and conflict ongoing, in addition to the risk of corruption or political instrumentalization of European prisoners. Again, it is hard to imagine a worse place in the world where Europe’s “most dangerous” individuals could be held. In line with their non-repatriation policy, and to address the aforementioned concerns, European governments are exploring the possibility to improve detention conditions and to strengthen “deradicalization” programmes in detention facilities. But it is hard to imagine how “deradicalization”, which is already deemed an extremely challenging endeavour based upon questionable assumptions in Europe, could succeed in such environment. As to the improvement of detention conditions, it is certainly needed, but it will not fundamentally address all the security concerns mentioned above. Finally, it is also important to remind that many European fighters will likely be sentenced EGMONT Royal Institute for International Relations 7