As conflicts intensify in the Middle East and other global flashpoints, law enforcement leaders across the United States and Canada must confront a sobering reality: the threat posed by ideologically driven sleeper cells operating within our borders is no longer hypothetical — it may be imminent.
These are threats that are designed to stay below the radar — highly disciplined operatives who embed quietly, avoiding detection until activation. Detecting such threats requires far more than traditional policing methods. It demands robust intelligence sharing, cross-jurisdictional coordination, community engagement and cutting-edge surveillance capabilities.
What is a sleeper cell?
A sleeper cell is a clandestine group of operatives often tied to a foreign government or extremist organization that seeks to remain inactive or “dormant” within a target country until they are activated to carry out a mission. These individuals typically live inconspicuously in society, blending into local communities — sometimes for years — while awaiting orders to engage in acts such as terrorism, sabotage, espionage or targeted violence.
What makes sleeper cells particularly dangerous and difficult for law enforcement to detect is their ability to remain hidden in plain sight. Unlike impulsive or lone-wolf actors, sleeper cell members are often highly trained — sometimes in military tactics or intelligence operations. They are strategically patient, willing to wait years before acting. They are well-resourced, supported by foreign state or transnational networks.
Their mission is rarely spontaneous. It is planned, coordinated and designed for maximum impact — often timed to align with geopolitical developments or broader ideological goals.
A shift in threat focus
Over the past five years, homeland security priorities have rightly shifted toward combating the growing threat of domestic violent extremism — particularly white supremacist and sovereign citizen movements. However, this necessary pivot has come at a cost. Until recently, our counterterrorism posture toward foreign-directed threats has eroded. The pendulum swung so far toward domestic concerns that agencies risked underestimating the reemergence of a far more organized and lethal adversary: foreign-trained operatives who have exploited border vulnerabilities and remained dormant, waiting for the right geopolitical trigger.
These individuals are not radicalized loners or disaffected youth — they are multilingual, militarily trained professionals equipped to conduct high-impact operations with precision and planning. Their goal is not chaos for its own sake, but strategic disruption, political destabilization and psychological terror.
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A warning from Mumbai
The 2008 Mumbai attacks were a watershed moment in modern terrorism. Over just 60 hours, 10 Lashkar-e-Taiba operatives executed a coordinated assault on multiple soft targets such as hotels, transit hubs, a café and a Jewish community center — crippling a major global city under the direction of overseas handlers.
That level of coordination is not only possible in North America — it is plausible. Intelligence sources in both the U.S. and Canada have confirmed past surveillance of Jewish, Israeli and Western-affiliated targets by Iran-aligned operatives. Should geopolitical tensions escalate further, our cities, places of worship and cultural centers could become the next front line.
PARIS ATTACKS: On November 13, 2015, a series of coordinated terrorist attacks were carried out in Paris by an ISIS-linked sleeper cell (SC), targeting six locations — including a concert hall, cafés and the national stadium — and resulting in 130 deaths and hundreds of injuries in a calculated assault meant to terrorize civilians across Europe.
The operational gap
After 9/11, U.S. and Canadian law enforcement made historic investments in homeland security and counterterrorism. But much of that infrastructure was designed to respond to threats of the past, not the emerging threat landscape of today. While agencies have focused — rightly — on active shooter prevention and lone-wolf attacks, few are currently trained or resourced to counter foreign-directed, multi-site paramilitary assaults.
Some sleeper cell operatives may now be trained in the use of unmanned aerial systems (UAS), including drones as weapons of mass destruction (WMDs). Most state, local and tribal agencies lack the legal authority, airspace jurisdiction or technology to interdict such an attack.
Compounding the threat, recent political and budgetary pressures have led some departments to scale back or dismantle tactical units and heavy response capabilities in the name of reform — leaving law enforcement less prepared for high-impact, coordinated attacks.
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Scenario-based preparedness is critical
Too few agencies are conducting realistic training that simulates:
- Coordinated, multi-site attacks
- Urban hostage situations
- Maritime or cross-border infiltrations
- Assaults on critical infrastructure or religious institutions
Frontline officers and mid-level commanders may not be trained to detect early warning signs such as encrypted communications, cyber probing, suspicious travel or prolonged surveillance. Communication and interoperability challenges remain.
Equally concerning is that many private security personnel assigned to protect schools, synagogues, mosques and community centers — among the most likely soft targets — are often undertrained, under-resourced and excluded from coordinated planning efforts. Yet in a crisis, these individuals are not only the first to respond — they may be the final line of defense before law enforcement arrives.
Once skeptical of “If You See Something, Say Something,” I’ve become one of its strongest proponents. Civilian situational awareness training is not a supplemental activity — it is essential. Unfortunately, many of these programs were shelved in recent years. They must be restored, expanded and adapted for today’s threat environment.
Six critical imperatives for law enforcement leaders
To confront the evolving threat of sleeper cells, law enforcement leaders must take decisive action across six key areas:
- Acknowledge the threat publicly: Sleeper cell activity is a credible and near-term risk. Silence or political discomfort invites complacency. Revive and expand community-facing programs like See Something, Say Something and Crime Stoppers to empower public vigilance.
- Expand tactical training paradigms: Move beyond single-shooter drills. Agencies must invest in scenario-based exercises simulating complex, coordinated terrorist operations involving SWAT, EMS, intelligence units and private security partners.
- Strengthen intelligence pipelines: Fusion centers and Joint Terrorism Task Forces must deepen coordination with local agencies. Information-sharing must be timely, contextualized and bidirectional.
- Harden religious and symbolic targets: Conduct vulnerability assessments and increase patrol visibility around synagogues, churches, mosques and Israeli-linked institutions. Ensure dispatch centers treat calls from these sites as priority infrastructure incidents.
- Rebalance the threat picture: Law enforcement must adopt a “think globally, act locally” mindset. Domestic extremism remains a critical concern, but foreign-directed terrorism is resurging. Threat assessments must reflect both, ensuring resource allocation matches the scope of the challenge.
- Prepare for drone-based threats: Provide training, technology and legislative support for law enforcement agencies to develop counter-UAS capabilities. We must anticipate drone swarms and WMD delivery mechanisms as viable attack vectors.
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A call to leadership
The threat landscape has changed, and our response must evolve accordingly. Sleeper cells and foreign-directed threats are not distant hypotheticals. They are methodical, patient and deliberate. They are not preparing for chaos — they are preparing for impact. And they are counting on our distraction, division and delay.
As police chiefs and sheriffs, the burden of preparedness ultimately rests with us. The professionals under our command continue to respond with skill, dedication and courage — but confronting this new generation of threats will require more than operational excellence. It demands leadership, strategic investment and a renewed commitment to training and coordination.
Preparing for the unthinkable is not fearmongering. It is responsible policing. The question is no longer whether sleeper cells are present — but whether we are prepared to meet the challenge they pose.
