There is no doubt that the Islamic State of Iraq and Sham (ISIS, also known as ISIL) is a threat to stability and security in Syria, Iraq and the broader Middle East. ISIS uses terrorist methods and commits gross violations of international humanitarian law and human rights. A US-led coalition against ISIS has been created with more than 60 partner states, along with organizations such as the EU and NATO, to counter ISIS.

In fact ISIS is not a newly emerged phenomenon. The UN Human Rights Council has been pointing out the presence of extremist groups, and specifically ISIS, in Syria since the beginning of 2013. The number of extremist groups began to grow after the invasion of Iraq in 2003, and as a result of the policies of subsequent governments that excluded important social segments of the nation. Turkey declared ISIS a terrorist organization and listed its name as such in its Official Gazette on October 10, 2013.

ISIS came to the attention of the world in the summer of 2014, when it captured the Iraqi city of Mosul and attacked Erbil, Kirkuk and Baghdad. The security of the oil regions and the minority Yazidi population became an international concern and focus of the international media. When Mosul was attacked, ISIS members captured 49 personnel of the Turkish Consulate. Turkey preferred diplomatic means for rescuing its personnel, and they were released after 101 days.

In August 2014, the UN Security Council adopted Resolution 2170 to counter ISIS. The resolution called on member states to take national measures to prevent the movement of terrorists, as well as to halt the supply of arms and financial support. However, no resolution authorizing the use of military force against ISIS has yet been adopted. Furthermore, although a coalition has been established with the participation of a wide range of countries, it is not clear what specific role each partner will play.

Countering ISIS is crucial and must be based on legal grounds as well as moral and ethical ones. The UN Charter, under Article 2(4), makes it illegal to use force against the territorial integrity and political independence of any state. There are two exceptions contained in the Charter; namely: Authorization by the Security Council (Art. 42), or Self-defence (Art. 51).

It could easily be claimed that due to the right to veto given to permanent members, any authorization of the use of force by the Security Council, including air strikes against ISIS, especially in Syria, does not seem possible.

Under the terms of Article 51 there must occur an armed attack to constitute the need for self-defence. It is not necessary that the armed attack be conducted by a state. It is possible to use self-defence against an armed attack by a non-state entity such as a terrorist group. However, military response must be proportionate. Self-defence can also be used collectively, i.e. with the participation of other states, upon a call by the state under attack.

Consent of any state to the use of force by other states within its territory definitely prevents the breach of Article 2(4). In other words, if the host state invites other states to use force within its territory, there cannot be a breach of the ban on the use of force.

It appears that the use of force against ISIS in Iraqi territory may be justified on the basis of an invitation by the Iraqi government, either within the context of self-defence or by consent. However, it is clear that there is a strong opposition to and condemnation of such action by Syria. It is perhaps for this reason that leading partners of the coalition, such as the UK and Canada have passed parliamentary motions permitting use of force only in Iraq, not Syria.

On the other hand, the US and some Arab coalition members continue air strikes in Syria. This action has to be examined from a legal point of view. There exists another legal avenue to be explored: Responsibility to Protect (R2P). Although its legal status and scope is not immune from criticism, according to the UN Office of the Special Adviser on the Prevention of Genocide, R2P has three pillars:

1. The State carries the primary responsibility for protecting populations from genocide, war crimes, crimes against humanity and ethnic cleansing;
2. The international community has a responsibility to encourage and assist States in fulfilling this responsibility;
3. The international community has a responsibility to use appropriate diplomatic, humanitarian and other means to protect populations from these crimes. If a State is manifestly failing to protect its populations, the international community must be prepared to take collective action to protect populations, in accordance with the Charter of the United Nations.

Military actions in Northern Iraq (1991), Kosovo (1999) and Libya (2011) are quoted as the well-known examples of R2P. It is possible to apply R2P against ISIS since the terrorist organization commits indiscriminate killing and deliberate targeting of civilians, mass executions and extrajudicial killings, persecution of individuals and entire communities on the basis of their identity, kidnapping of civilians, forced displacement of local communities, killing and maiming of children, rape and other forms of sexual violence, along with numerous other atrocities.

ISIS is not alone however in these grave breaches of international human rights law and humanitarian law in Syria. In addition to the above-mentioned crimes committed by ISIS, the Assad regime has employed other forms of brutality including the use of barrel bombs, chemical weapons, and starvation as a method of warfare along with many others. These acts are very well recorded and documented.

There cannot be a reasonable explanation why R2P should not be applied against the Assad regime if it is ever going to be applied against ISIS. Indeed, more than 200 thousand people have lost their lives in the fighting in Syria since 2011, more than 4 million Syrians have had to seek asylum outside their own county, and more than 6.5 million have been internally displaced.

R2P must not be applied in a discriminatory manner. Everyone trapped in Syria both in the hands of Assad or ISIS must be given humanitarian assistance and protection. The establishment of safe areas in Syria where civilians can live and to which refugees can return is a must for humanitarian reasons. Without such havens, it is not possible to extend full protection. To establish safe areas, if no Security Council resolution is going to be secured, the UN General Assembly might be used as a platform,

If such a considerable number of states come together and create a coalition as mentioned above, an adoption of a resolution by the General Assembly should not be a problem. If not, coalition member international organizations, namely NATO and the EU, should take the initiative outside the UN together with other states and regional organizations.

Turkey has shown that it is ready to help the peoples of Syria and Iraq, since the government has been given power by the parliament to use its military, if needed, for the protection of civilians. Turkey is now waiting for the coalition to make its position clear.