“If Allah wants, it will come back tomorrow. If Allah wants, it will be a little longer. It is just a matter of time,” boasted a defiant German recruit of the Islamic State (IS) terror group. “If it belongs to Sharia [Islamic law], then there is nothing to complain about,” she said, defending the beheadings and other atrocities committed by the group in Iraq and Syria in an interview with the UK newspaper the Daily Mail on Saturday. “If there is war, there is killing,” she insisted. As Iraq and Syria continue to battle IS after the terrorist group lost control of its final footholds in the two countries, questions remain about whether the world is doing enough to punish the group's remnants and especially returning fighters. Fear of de facto impunity being granted to the fighters has been highlighted in recent weeks after the United States, Europe and countries across the world have demonstrated an unwillingness to accept returning IS militants and prosecute them in the courts. Reports of IS women and children trapped in prisons in Iraq and camps in Syria facing an uncertain future have also brought to the fore the debate over what to do with former IS fighters. Large numbers of IS fighters in Iraq and Syria have been either killed or captured, but thousands are believed to have gone underground or to have fled the two countries. The phenomenon has given way to a pressing question: what the world should do with foreign IS fighters to make sure that it pulls its weight in the war on terrorism. Already, the United States and European countries have showed little political will to allow former IS fighters to return. The two decided last week to bar two IS mothers from returning to their countries of origin, saying they posed a risk to national security. The debate took a sharp twist after US President Donald Trump asked Britain, France, Germany and other European allies to take back over 800 IS fighters that US troops had captured in Syria and to put them on trial. Trump warned that the only other option would be to release the fighters, allowing them to seep back into Europe and pose a security threat to the continent. A July 2018 study by the International Centre for the study of Radicalisation (ICSR) at King's College London concluded that 41,490 people from 80 countries were affiliated with IS. ICSR research based on official, academic and other data found that at least 7,366 foreigners affiliated with IS had travelled back to their own countries, including 256 women and up to 1,180 children. By June 2018, 3,906 people had returned to countries in the Middle East and North Africa, 1,765 to Western Europe, 784 to Eastern Europe, 338 to Central Asia, 308 to Southeast Asia, 156 to Southern Asia, 97 to the Americas, Australia and New Zealand, and 12 to Sub-Saharan Africa, it said. There has been no word thus far on trials or investigations of these returnees, and governments have remained largely silent on plans to deal with the problem. Some European governments have made it clear that they are not ready to take back their nationals who they believe might create a danger to their national security. The UK has found a way to circumvent the issue, at least as far as dual nationals are concerned, by revoking the citizenship of more than 100 people who have been stripped of their British passports. The United States, meanwhile, has decided to ban Hoda Muthana, a woman from Alabama who left to join IS in 2014, from returning to the country by claiming that she had no right to US citizenship in the first place. France, Germany and other European countries have been reluctant to accept the repatriation of their nationals who are among the foreign jihadi fighters and may pose a threat to them. Only a small number of nations, including Indonesia, Lebanon, Morocco, Russia, Sudan and Tunisia, have allowed IS followers to return from Iraq and Syria, though it is not clear how many have been investigated or have faced legal action. Millions of Iraqis and Syrians who suffered from IS brutality when the terrorist group controlled vast chunks of their territory for some four years have seen little or no action on the ground to bring justice to the victims of crimes committed by IS terrorists. The group is still pursuing its campaign of terror in many parts of Iraq. Attacks and bombings continue to occur throughout the country, and remnants of IS still hold territory in remote and rural areas. On Saturday, five fishermen were slaughtered in the Thirthar Lake district west of the Iraqi capital Baghdad by IS terrorist two days after the group killed six men who were trekking in the desert during the mushroom-picking season. In both attacks the victims were Shia Muslims who were specifically targeted as part of a renewed IS tactic to reignite the sectarian tensions in Iraq that killed hundreds of thousands of people in the civil struggle that erupted after the US-led invasion of Iraq in 2003. Despite efforts by the Iraqi government to crack down on the group and prosecute its members, more than two years after Baghdad declared victory over IS many of its former supporters are believed to be free, and many Iraqis fear they might attempt a comeback. Security experts have also warned that a resurgent IS could target European cities for terror attacks using returning militants to carry out the assaults. Any impunity for IS terrorists for their crimes and abuses is a serious problem for justice and accountability in Iraq and Syria and for broader efforts at combatting international terrorism. Though some governments claim they are exploring ways to retrieve their nationals and probe their cases, their efforts are falling short of providing concrete and practical measures to punish the perpetrators of crimes and provide justice for IS victims. Some of these countries consider travelling to IS-held territory not to be a crime in itself, saying that it is not illegal to marry an IS fighter either. They also claim that finding evidence for serious crimes perpetrated by terrorists can be difficult. In order to confront the array of legal, political, diplomatic and security issues that are hampering efforts to deal with the seriousness of these crimes, the world should unite to deal with the problem as a global crisis. The answer to this question will determine the future of global counter-terrorism strategies in view of conflicting national priorities in the aftermath of the military successes to drive IS from key cities in Iraq and Syria. The controversy over the IS fighters has triggered concerns that the parties to the international war against IS lack a coherent strategy to track returning militants and bring them to justice. Without cooperation from states to build cases using both international and national laws to prosecute individuals for serious crimes, efforts to prosecute terrorists will surely suffer. The UN Security Council adopted a resolution in September 2017 to set up a team to investigate the massacre of the Yazidi minority and other atrocities by militants in Iraq. The resolution provides an international mechanism to bring those responsible for IS war crimes to justice. Yet, the attempt may be being stymied by a lack of cooperation by various parties because of international politics and national interests. The UN investigation team formed under the resolution to collect evidence of acts by IS that may be war crimes, crimes against humanity or genocide has been focusing on administrative and technical details to lay the groundwork for its probe. However, recent media reports about IS women returnees have put a spotlight on the future of the foreign fighters even if they were originally intended to be sympathetic to the women's ordeal. They underscored the need to end the indecision and to take bold initiatives to deal with the crisis. They underscored the need to end the indecision and to take bold initiatives to deal with the crisis. Iraqi President Barham Salih announcement on Monday that Baghdad is seeking IS militants “who have engaged in crimes against Iraq” to put them on “trial in Iraqi courts” seems to be rather a political statement than a legal commitment. At the heart of the problem, however, is the absence of strict and well-defined security and judicial mechanisms on both the national and international levels to address the problem. Many sceptics now fear that providing justice for IS victims will not take place and the dark side of recruiting and transferring thousands of would-be terrorists from around the world to Iraq and Syria might never come to light.