One of the most significant common factors that has characterized the Arab world in recent years has been the birth and spread of non-state actors – organizations, parties, militias – that have assumed the role of traditional governments in many countries. 
These non-state actors do not follow a single pattern of behavior, but they do highlight a common trend across much of the Arab world, namely the continuing fragmentation of once whole, sovereign states into a patchwork of armed groups that operate within their borders.
The most extreme cases are Iraq, Syria, Yemen, Libya, Lebanon and Somalia, where state authority has been replaced in large areas by the power of armed groups. The most dramatic example is ISIS, which has taken control of a large swath of land across the northern expanses of those two countries.
Others include Al-Shabab in Somalia, the Houthis in Yemen,Hezbollah in Lebanon, Hamas in Palestine, several large militias in Libya, a patchwork of rebel groups in Syria other than ISIS, and other smaller groups across the region. 
This combination of retreating state authorities and surging non-state powers is common across the region, but it is also very difficult to apply a single analysis that uniformly explains why this is going on. Rather, it is more useful analytically to ask about a series of sub-state factors when examining the development of groups such as ISIS, Hezbollah, the militias in Iraq or Hamas and many others.
I would suggest that seven issues in particular need to be applied in order to gauge the real power and longevity of these non-state actors, alongside the dilution of state authority. These seven are Identity, Sovereignty, Territoriality, Service-delivery, Legitimacy, Nationality and Statehood. 
One important reason why so many Arab states are fragile and turbulent is that these factors have never coincided naturally, as they must for there to be stable, satisfying and durable statehood – a rare feat in the modern Arab world. 
So we can assess a group like ISIS as controlling territory and reflecting important identity elements among its adherents, thus enjoying semi-sovereignty in its areas of control. But it is hard to see the group as legitimate because most of the people under its control did not assent to ISIS rule. 
Similarly, Hezbollah reflects important identity elements among its mostly Lebanese Shiite adherents. It is also fully legitimate in the eyes of its supporters, as well as among many Lebanese on the strength of its being represented in the government and Parliament. But it does not aspire to its own state, nationalism or formal sovereignty, even as it simultaneously reflects elements of those phenomena by the fact that it enjoys full control of land, people and resources in its core areas. 
Hezbollah, like Hamas and other Islamists and many large non-governmental organizations working at community level, offer important services that citizens want (health and welfare, food, social support to families, security) – but this service delivery in itself is not a basis for governing legitimately.
The fragmentation and occasional collapse of some Arab states in recent years force us to come to grips with the reality that we should not assess Arab countries through the traditional lens of statehood, where a geographically delineated land and its inhabitants formed a single state or nation whose sovereignty was managed by the government. More significant nowadays are the dynamics captured in these seven sub-state phenomena that ultimately define whether a state, community or citizen exists in a healthy and lasting manner. 
The single most important of the seven, in my view, is legitimacy. This is the glue that binds a citizen to his or her state, which in turn shapes the extent of nationhood, statehood and sovereignty in any particular case. 
The problem with all Arab countries, without exception, is that they have never given their citizens opportunities to legitimize their states, for example by writing their own constitutions and defining their national power structures, values and accountability mechanisms. 
So we ended up with countries that enjoyed strong central governments and ruling elites based on the support of their massive militaries and police systems. However, these countries’ governments usually lacked legitimacy because the power vested in the ruling elite and its soldiers lacked the validating force of the participation and consent of the citizenry.
So when we see Arab countries today fragmenting into smaller units without necessarily creating new sovereign states, we should worry less about the fate of old borders and ask whether the new dynamics of armed populations reflect identity, service delivery and legitimacy in the eyes of their own people. Those are the factors that ultimately will determine whether certain people in a territory will be seen by the world as a state or a nation.