The Canadian debate about the fight against the Islamic State frequently involves the need to take a holistic approach – essentially a broad strategy that includes everything from training missions overseas to countering violent extremism programs at home.

But is this the right way to look at the IS problem?

It might be tempting for the new federal government to present its strategy as a “whole of government” approach, but treating Islamic State as a puzzle that can be addressed in a comprehensive way is problematic. IS is a complex, dynamic and multifaceted organization that has managed to defy efforts to eliminate it and transformed itself into arguably the most sophisticated counterterrorism challenge faced by the West.

In fact, Islamic State should be broken down into two components: a sophisticated leadership controlling operations in Iraq and Syria; and the rank and file that actively support it.

The leadership, although extremist, has managed to learn and adapt in the face of years of counterterrorism pressure against it. Even if it is eventually removed (or contained) in Iraq and Syria, we can expect that the leadership will continue to exploit ungoverned and undergoverned places, including parts of North Africa and South Asia.

On the other hand, the membership of IS, including an estimated 25,000 to 30,000 fighters, is the direct result of the group’s leadership lowering the traditional barriers to entry into a terrorist organization. Whereas al-Qaeda, an elitist and security-conscious group, has strict membership standards that normally require some form of vetting process, the Islamic State policy has been to welcome the thousands it inspired.

In this way, IS has transformed into the world’s first modern terrorist mass-movement. Less sophisticated than its leadership, the general membership poses a threat by its sheer size. Recruits are drawn to the organization not only for its extremist message, but also its promise of adventure, military training, money, wives (or husbands), and life under a pure caliphate.

It is vital that policy-makers recognize that, for Canada, this manifests in four distinct threats.

First, Islamic State is a source of instability in the Middle East that threatens our allies. Although IS might not be the primary source of refugees and the current humanitarian crisis, it has contributed to the suffering of millions of civilians. This is the threat that the new military strategy and training mission aim to counter.

However, there is a serious risk that the situation overseas will soon get worse. IS is looking to set up shop in unstable regions of the world. Not only will this further destabilize these already fragile areas, but IS will also gain access to established networks that can provide access to illicit material and channel individuals to and from zones of conflict and instability.

The second threat is posed by foreign fighters. The primary risk for Canada comes from its own citizens travelling abroad to join IS. It might seem strange to want to stop extremists from leaving Canada, but there are important security reasons to do so. While overseas, these individuals are likely to be further radicalized and help to further the aims of an extremist organization. They also gain access to military-style training, which they use in the fight against our allies and to intimidate civilian populations. There is also a risk that these trained individuals (or others using their Western passports) will be sent to another country, particularly in Europe, or back home to Canada where they will conduct an attack. The November, 2015, attacks in Paris are a tragic reminder of the risk that foreign fighters pose to Canada.

Third, as a mass movement, IS seeks to spread its propaganda, radicalizing individuals in Canada and the West. There is no known model of radicalization, but individuals might be drawn to IS through wannabe authority figures who draw upon its message; through networks of friends who polarize together; and through IS recruiters who seek out and target vulnerable people who may have expressed sympathy or support through social media. The IS message sows mistrust, dividing and hurting families and community institutions.

Finally, and arguably the most important for Canada’s national security, is the risk of domestic terrorist activity – an attack by individuals directed, approved or inspired by IS within Canada. This could be an armed attack by trained foreign fighters, but there is also the risk that IS-inspired individuals who are prevented from travelling abroad by Canadian authorities might feel compelled to act in some way.

And there are other types of domestic terrorist activities, beyond armed attacks. This includes people in Canada who try to support IS through financing (with their own and/or illicit funds) or those who try to facilitate its activities, such as providing logistical and material support to those who want to fight overseas.

There is no question that many of these threats are linked. IS can use its overseas bases as training and planning grounds to launch attacks against the West. A few radicalized individuals might seek to become foreign fighters, or to conduct attacks at home. However, this does not mean the solution to the threats should be considered as a whole.

Canada is facing not one, but four, fights against Islamic State. Each of these four threats requires a separate response.

The Canadian government must understand the multifaceted nature of the fight against IS, and ensure that its future policies deal with each of the four threats. Although mutual consultation about the nature of the threats is vital, Ottawa must ensure its approach does not conflate the four related, but distinct, threats posed by one of the most deadly terrorist organizations in modern history.