The Fifth Wave of Terrorism May Not Be Terrorism at All: Understanding the Rise of the Hybrid Grievance Threat

Understanding the rise of the Hybrid Grievance Threat

Throughout my university studies, one of the frameworks that consistently resonated with me was David Rapoport's Four Waves theory of terrorism. Like many students of terrorism and political violence, I appreciated its simplicity and explanatory power. It provided a compelling lens through which to understand how modern terrorism evolved through successive eras dominated by anarchist, anti-colonial, new-left and religious movements.

Years later, after a career spanning military service, protective security, threat assessment and security risk management, I still regard it as one of the most influential frameworks ever developed in terrorism studies. It remains highly relevant and continues to shape the way governments, academics and practitioners think about politically motivated violence.

However, the more time I spend assessing contemporary threats, the more I find myself questioning whether the threat environment we face today can still be adequately explained through ideological models alone.

The individuals confronting security practitioners today rarely fit neatly within established categories.

Some display characteristics traditionally associated with terrorists. Others resemble fixated persons, workplace violence offenders, lone actors, ideologically motivated extremists or aggrieved insiders. Increasingly, many appear to be several of these things at once.

This observation has led me to a simple question.

What if the emerging Fifth Wave is not defined by a new ideology at all?

What if the defining feature of the next wave is not what people believe, but rather the convergence of grievance, fixation, identity and mobilisation within digitally amplified environments?

What if the common factor is not ideology, but grievance?

This is what I have come to think of as the Hybrid Grievance Wave.

The Issue with Labels

One of the recurring challenges in contemporary threat assessment is our tendency to categorise people.

We often strive to determine whether someone is a terrorist, a violent extremist, a lone actor, a fixated person, a workplace violence offender or an aggrieved insider.

These categories remain useful.

However, in practice, reality is rarely that tidy.

Over the years I have reviewed incidents, case studies and threat reports involving individuals who moved freely between multiple ideological, political and social narratives. Some were driven by political grievances. Others by personal resentment, perceived injustice, identity struggles or social isolation. Many adopted ideological narratives only after their grievances had already developed.

The more I examined these cases, the more I began to notice a common pattern.

The grievance remained constant.

The ideology changed.

This is particularly evident among contemporary actors who may simultaneously:

• Hold anti-government beliefs.

• Subscribe to conspiracy theories.

• Express racial or cultural grievances.

• Demonstrate intense personal resentment.

• Exhibit fixation or obsession.

• Consume content from multiple extremist ecosystems.

• Lack meaningful affiliation with any organised movement.

In such cases, ideology may be present, but it is not necessarily the primary driver.

More often, ideology appears to act as a vehicle through which pre-existing grievances are expressed and legitimised.

There Is No Longer a One-Size-Fits-All Threat Model

One of the most significant lessons I have learned throughout my career is that threat actors rarely present in the way our frameworks expect them to.

Security practitioners understandably seek consistency. We develop categories, methodologies and indicators to create order and assist decision-making.

Yet contemporary threat actors increasingly challenge those boundaries.

Some exhibit elements of terrorism without belonging to a terrorist organisation - others are highly fixated but politically disengaged.

Some possess strong ideological beliefs yet display little evidence of mobilisation - others display clear mobilisation indicators despite lacking coherent ideological convictions.

This is why I have become increasingly cautious about one-size-fits-all approaches to threat assessment.

The reality is that every threat pathway is different. Every grievance develops differently.

Every mobilisation pathway unfolds differently. Every subject presents differently.

The challenge for practitioners is therefore not determining which category an individual belongs to ... the challenge is understanding how that particular individual's pathway to violence is unfolding.

The Digital Acceleration of Grievance

The internet has fundamentally changed the threat landscape.

Previous generations of extremists typically radicalised through physical organisations, charismatic leaders or disciplined movements.

Today, individuals increasingly self-select into violence through digital ecosystems.

Online environments provide:

• Reinforcement of perceived grievances.

• Continuous exposure to outrage and victimisation narratives.

• Access to multiple ideological communities.

• Instant validation from anonymous networks.

• Guidance on attack methodologies.

• Amplification of notoriety and recognition.

As a result, mobilisation no longer requires formal recruitment.

Many contemporary actors do not require a leader. They do not require membership.

They do not require organisational direction. They simply require a grievance, an audience and a pathway.

Increasingly, violence has become self-authorised.

From Ideological Assessment to Behavioural Assessment

Perhaps the biggest shift I have observed over the past decade is the growing importance of behaviour over ideology.

Traditional counter-terrorism approaches often begin by asking:

What does this person believe?

Modern threat assessment increasingly begins with a different question:

What is this person doing?

In practice, the most concerning individuals are often not those with the strongest ideological convictions.

They are the individuals displaying:

• Escalating grievance.

• Increasing fixation.

• Identity fusion with a cause or issue.

• Leakage behaviours.

• Triggering life events.

• Mobilisation activity.

• Capability development.

• Opportunity seeking.

Importantly, these indicators appear across numerous threat categories:

• They are observed in terrorism.

• They are observed in targeted violence.

• They are observed in workplace violence.

• They are observed in school attacks.

• They are observed in fixated person incidents.

• The behavioural overlap is becoming increasingly difficult to ignore.

The Characteristics of the Hybrid Grievance Wave

If a Fifth Wave is emerging, I do not believe it will be defined by a single ideology.

Rather, it will likely be characterised by several recurring features.

Grievance Convergence

Personal, social, political and ideological grievances merge into a single narrative of perceived injustice.

Ideological Fluidity

Individuals move between narratives and belief systems rather than remaining committed to one ideology.

Digital Mobilisation

Online environments become the primary mechanism for reinforcement, radicalisation and validation.

Self-Directed Violence

Actors increasingly mobilise independently of structured organisations.

Fixation and Obsession

Persistent focus on people, institutions, groups or symbolic targets becomes a common pathway.

Symbolic Amplification

Attacks are designed not only to create harm, but to generate attention, influence and notoriety.

Implications for Protective Security

If the Hybrid Grievance Wave accurately reflects the contemporary threat environment, then protective security frameworks must continue to evolve.

Rather than focusing solely on ideological categorisation, practitioners should place greater emphasis on:

• Grievance development.

• Fixation indicators.

• Mobilisation behaviours.

• Capability.

• Intent.

• Triggering events.

• Leakage.

• Opportunity pathways.

This does not mean ideology is irrelevant.

Far from it.

Ideology remains an important component of threat assessment.

However, it is increasingly only one component of a far broader risk picture.

The individual who poses the greatest threat may not be the most ideologically committed ... they may instead be the most aggrieved, most fixated and most mobilised.

Looking Ahead

Whether history ultimately recognises a Fifth Wave remains uncertain.

However, after years of studying terrorism and working within the security profession, one conclusion feels increasingly difficult to ignore.

The distinctions that once separated terrorism, lone actor violence, workplace violence, fixated person incidents and other forms of targeted violence are becoming progressively blurred.

The pathways toward violence are converging.

The traditional categories remain useful, but they are becoming less effective as standalone explanations for contemporary threats.

If the twentieth century was shaped by competing ideologies, the coming decades may be shaped by something different.

Not a wave defined by doctrine.

Not a wave defined by membership.

Not a wave defined by organisational allegiance.

Instead, a wave defined by grievance.

A wave in which individuals adopt whatever narrative best validates their perception of injustice.

A wave in which fixation, identity and mobilisation matter as much as ideology.

A wave in which there is no single threat profile, no single pathway and no one-size-fits-all explanation.

Perhaps that is the defining feature of the Fifth Wave. Not the emergence of a new ideology.

But the collapse of the idea that a single ideology can explain the threat at all.