The year 2026 will mark the 25th anniversary of the September 11, 2001 attacks, a milestone that has renewed concerns among security analysts about the potential symbolic use of the date by Salafi-Jihadist groups like al-Qaeda and ISIS. These worries are intensified by patterns of terrorist violence and broader political and social shifts seen throughout 2025, which collectively suggest an increasingly fragmented and unpredictable threat environment. In this context, Western countries—including the U.S., Europe, and Australia—may once again face heightened risks as prime targets for both transnational jihadist networks and ideologically motivated lone actors seeking symbolic impact. This article examines major terrorist attacks and emerging threat trends in these regions in 2025, highlighting how decentralized actors, ideological hybridity, and diverse tactics could influence terrorism risks as 2026 begins.
United States: Decentralized and Lone-Actor Terrorism
Terrorist violence in the United States during 2025 demonstrated a fragmented but persistent threat environment, characterized primarily by lone-actor attacks, tactical diversity, and overlapping ideological, religious, and personal grievance motivations. Rather than coordinated organizational campaigns, most attacks were carried out by individuals inspired by extremist narratives or motivated by perceived grievances, targeting public spaces, transportation systems, and religious or symbolic sites.
Salafi-Jihadist–Inspired and Transnationally Motivated Attacks: A limited but significant subset of attacks in 2025 reflected inspiration from foreign terrorist organizations, particularly ISIS. The most lethal incident occurred on January 1 in New Orleans, Louisiana, where a vehicle-ramming and shooting attack during New Year’s celebrations killed 14 people and injured dozens. The perpetrator was reportedly inspired by ISIS ideology, underscoring the continued resonance of jihadist narratives among lone actors despite sustained counterterrorism pressure on organized networks. Similarly, the June 1 firebombing in Boulder, Colorado, in which Mohamed Sabry Soliman attacked participants in a solidarity walk using incendiary devices, reflected the intersection of international political grievances and extremist violence within the U.S. homeland.
Ideologically Motivated Domestic Terrorism: Several attacks in 2025 were rooted in domestic ideological extremism rather than foreign terrorist direction. On April 13, an arson attack using Molotov cocktails targeted the residence of Pennsylvania Governor Josh Shapiro, resulting in terrorism and attempted murder charges. While not linked to a foreign group, the incident demonstrated how political polarization and ideological radicalization continue to drive attacks against elected officials and government symbols. Similarly, the September 28 attack in Grand Blanc Township, Michigan, involving vehicle ramming, shooting, and arson at a Mormon church, reflected ideologically motivated violence against religious institutions perceived as symbolic or political targets.
Religious and sectarian targeting: Religious institutions and faith-based gatherings were repeatedly targeted in 2025, intensifying concerns about ideologically driven hate violence merging with terrorism. On August 27, a gun attack during a Catholic Mass at a church and school in Minneapolis, Minnesota, killed two children and injured more than twenty others, prompting authorities to investigate the incident as both domestic terrorism and an anti-Catholic hate crime. The Boulder firebombing also targeted members of the group “Run for Their Lives” gathering, illustrating how religious identity and geopolitical grievances increasingly intersect in antisemitic lone-actor attacks.
Public Spaces and Transportation as Recurrent Targets: Public venues and transportation systems remained frequent targets, reflecting attackers’ intent to maximize visibility and casualties. On July 27, a mass stabbing at a Walmart injured 11 people, while on August 22, a fatal stabbing occurred on a light-rail train in Charlotte, North Carolina, resulting in federal terrorism charges. On November 17, an attack on a subway train in Chicago, in which a woman was set on fire, was prosecuted as terrorism. These incidents illustrate the vulnerability of everyday public environments and mass transit systems to low-cost, high-impact attacks carried out by individuals.
Tactical Diversity and Low-Barrier Methods: Across all categories, 2025 attacks demonstrated a wide range of tactics, including vehicle ramming, arson, firebombing, improvised explosives, stabbings, and firearms. The May 17 car bombing at a fertility clinic in Palm Springs, California, and the January 1 car bombing in Paradise, Nevada, highlight the continued appeal of vehicle-borne explosives, even when used by lone actors. The prevalence of simple weapons—knives, vehicles, and incendiary devices—reinforces concerns that terrorism in the U.S. increasingly relies on accessible tools rather than sophisticated planning.
In addition to the surge of terrorist incidents in 2025, the United States began implementing notable shifts in counterterrorism policy, reflecting an expanded focus on both ideologically driven groups and economically motivated transnational criminal networks. Along with notable terrorist incidents in that year, the United States experienced significant shifts in its counterterrorism strategy during the second Trump administration, reflecting a broader and more flexible definition of terrorism. During this time, the U.S. government designated a historically high number of groups and organizations as terrorist entities, surpassing previous waves of designations after the September 11 attacks and the post–Arab Spring rise of al-Qaeda affiliates in 2011, many of which later evolved into ISIS and its global networks. This shift marked a change from the traditional focus on jihadist groups, as the designation process for the first time explicitly included economically motivated actors such as drug cartels, transnational smuggling and trafficking organizations operating in Mexico, Colombia, Venezuela, and Ecuador, and criminal gangs from Haiti and El Salvador. It should be noted, however, that while terrorist designations can expand U.S. authorities’ legal and military options—enabling overseas operations, sanctions, and more aggressive efforts to disrupt terrorist financing—they do not necessarily produce the expected outcomes in terms of dismantling or decisively weakening these organizations, particularly when such groups are deeply embedded in local economies, governance vacuums, and criminal networks.
The administration also targeted militia groups backed by Iran, including Harakat al-Nujaba (HAN), Kata’ib Sayyid al-Shuhada (KSS), Harakat Ansar Allah al-Awfiya (HAAA), and Kata’ib al-Imam Ali (KIA), as well as anarchist and revolutionary groups such as Antifa Ost, Informal Anarchist Federation/International Revolutionary Front (FAI/FRI), Armed Proletarian Justice, and Revolutionary Class Self-Defense. Other insurgent and separatist organizations, including the Balochistan Liberation Army (BLA), were also designated. Houthis in Yemen were added again to the FTO list after their attacks in the Red Sea targeting commercial ships following the October 7 Hamas terror attacks. In total, 25 groups have been classified as terrorist entities since February 20, 2025, reflecting a broadening of the terrorism threat landscape to include narco-terrorism, organized crime, and transnational insurgency, signaling a notably more inclusive approach to U.S. counterterrorism strategy in the mid-2020s.
This shift was also seen in military and kinetic operations abroad. Notably, U.S. airstrikes targeted drug trafficking boats linked to Tren De Aragua, a designated terrorist group, in the Caribbean Sea, ISIS in Syria, and the Islamic State–Greater Sahara branch in Nigeria’s northwestern Sokoto region, which was reported to have attacked Christian communities. However, analysts have warned that ISIS and its affiliates remain more deeply rooted in northeastern Nigeria, while many armed groups in the northwest are seen by Nigerian media and regional experts as criminal bandits rather than ideological militants. This distinction highlights the growing overlap between terrorism and organized crime, raising questions about the effectiveness and sustainability of counterterrorism strategies in areas where insurgency, criminal activity, and local conflicts intersect. Overall, these developments suggest that U.S. counterterrorism efforts in 2025 shifted toward a broader and more controversial view of threats, likely influencing policy debates and operational priorities as the U.S. moves toward 2026.
Europe: Hybrid Ideological and Lone-Actor Violence
Terrorist violence in Europe during 2025 reflected a continued pattern of lone-actor and small-cell attacks, driven by both Jihadist-inspired extremism and far-right ideology. As in the United States, most incidents were not centrally directed by hierarchical terrorist organizations. Still, they were instead carried out by individuals inspired by extremist narratives, often exploiting public spaces, symbolic locations, and moments of social gathering to maximize visibility and psychological impact.
Salafi-Jihadist–Inspired and Motivated Attacks: A significant portion of attacks in Europe during 2025 were carried out by individuals inspired by ISIS or broader jihadist ideology. On February 15, in Villach, Austria, a 23-year-old man linked to ISIS carried out a mass stabbing that killed a fourteen-year-old boy and injured five others. Days later, on February 21, in Berlin, Germany, a Syrian asylum seeker stabbed a Spanish tourist at the Memorial to the Murdered Jews of Europe, having reportedly planned the attack and expressed intent to target Jewish individuals. Jihadism-inspired violence continued on February 22 in Mulhouse, France, when a man stabbed multiple people, including police officers, during a protest after shouting religious slogans. On May 18, in Bielefeld, Germany, another ISIS-inspired attacker stabbed five spectators at a bar during a football match. These incidents underscore the persistent resonance of jihadist ideology in Europe despite years of counterterrorism pressure and the degradation of ISIS’s territorial control.
Far-Right and Ideologically Motivated Domestic Terrorism: Europe in 2025 also witnessed lethal violence driven by far-right extremism. On August 24, in Kampen, Oslo, Norway, an 18-year-old far-right assailant fatally stabbed Tamima Nibras Juhar, a Muslim welfare worker, and was found to have planned additional attacks targeting mosques. This incident highlights the ongoing threat posed by violent right-wing ideologies in Europe and reflects a broader pattern of reciprocal radicalization, in which Islamist and far-right extremist narratives reinforce one another across digital and social spaces.
Targeting of Symbolic, Religious, and Identity-Based Sites: Several attacks in 2025 deliberately targeted symbolic or identity-laden locations, reinforcing terrorism’s communicative and psychological dimensions. The stabbing at Berlin’s Holocaust memorial represented a direct assault on a site of historical memory and Jewish identity, while attacks at protests, sports venues, and community spaces emphasized the vulnerability of everyday social environments. The selection of such targets mirrors trends observed in the United States, where attackers seek not only casualties but also symbolic resonance and media amplification.
Coordinated and Infrastructure-Focused Attacks: While most European attacks were carried out by individuals, 2025 also saw limited examples of coordinated operations. On April 13, a series of arson and firearm attacks collectively known as the 2025 French prison attacks targeted penitentiary-related sites across France. Although not mass-casualty events, these attacks demonstrated a higher level of organization and strategic intent, aimed at disrupting state institutions and projecting operational capability. Such incidents suggest that while lone actors dominate the threat landscape, small networks retain the ability to coordinate symbolic and disruptive actions.
Tactical Simplicity and Low-Barrier Methods: Similar to the United States, attackers in Europe relied heavily on low-cost, easily accessible weapons like knives and arson tools. The prevalence of stabbings reflects both firearm restrictions and the effectiveness of simple methods in crowded public areas. This straightforward approach complicates detection and prevention because such attacks require little preparation and can be carried out quickly with minimal logistical support. The 2025 attacks demonstrate that Europe continues to face a hybrid terrorism threat environment characterized by decentralized violence, diverse ideologies, and mutual radicalization. Jihadist-inspired and far-right groups increasingly operate within the same ecosystem of grievances, polarization, and online propaganda, targeting public spaces and symbolic locations to maximize psychological impact.
Australia: Dual Threats from Jihadist and Domestic Extremism
Terrorist violence in Australia during 2025, while limited in number, reflected a dual threat environment characterized by both transnational jihadist-inspired attacks and domestic anti-government extremism. As in the United States and Europe, incidents were primarily driven by individual actors or small cells rather than by coordinated organizational campaigns, highlighting the challenges of detecting and preventing low-frequency yet high-impact attacks.
Salafi-Jihadist–Inspired and Transnationally Motivated Attacks: Australia experienced one of its deadliest jihadist-inspired attacks in recent years on December 14, when two gunmen linked to the ISIS carried out a mass shooting on Bondi Beach in Sydney during a Hanukkah celebration. The attack killed 15 people and injured dozens more, deliberately targeting a crowded public and religiously symbolic setting. One attacker was killed at the scene, while the second was apprehended in critical condition. Subsequent investigations uncovered two improvised explosive devices in a vehicle linked to the attackers, underscoring the continued intent of ISIS-inspired actors to combine firearms with explosives to maximize casualties and psychological impact. The incident demonstrated that, despite Australia’s geographic isolation and robust counterterrorism apparatus, transnational jihadist ideology continues to resonate with a small but dangerous subset of individuals.
Anti-Government and Sovereign Citizen Extremism: In contrast to jihadist violence, Australia also faced lethal domestic extremism rooted in anti-government ideology. On August 26, in Porepunkah, Victoria, a self-proclaimed sovereign citizen opened fire on police officers executing a warrant related to a firearms prohibition order, killing two officers and injuring a third before fleeing the scene. The attack reflected a broader pattern of anti-state radicalization observed in several Western democracies, in which individuals reject governmental authority, legal systems, and the legitimacy of law enforcement.
Both major incidents in Australia during 2025 involved attacks on public or semi-public settings, reinforcing a recurring global pattern. Bondi Beach, a highly visible and internationally recognized location, was selected for its symbolic value and high foot traffic, while the attack on police officers occurred during the execution of official duties, directly challenging state authority. These targeting choices reflect attackers’ intent to generate fear, media attention, and symbolic resonance rather than solely tactical gains. The Australian cases also illustrate tactical diversity similar to that seen in the United States and Europe. Firearms were the primary weapons in both attacks, but the discovery of improvised explosive devices following the Bondi Beach shooting indicates an escalation potential beyond the initial assault. The combination of shooting attacks with explosives aligns with ISIS-inspired operational playbooks and raises concerns about future attempts to conduct multi-stage or mass-casualty operations in Australia.
Looking Ahead to 2026
Based on patterns observed in terrorist activity across the United States, Europe, and Australia in 2025, the threat environment heading into 2026 is likely to remain persistent but fragmented, shaped primarily by lone actors and small, informal networks rather than centrally directed terrorist organizations. Security pressure on structured jihadist groups has reduced their capacity for complex external operations, yet ideological narratives—particularly those associated with Salafi-jihadism and post October 7 Hamas terror attacks—continue to inspire individuals to act independently, sustaining a baseline level of risk across Western countries.
The twenty-fifth anniversary of the September 11 attacks may hold symbolic significance for extremist propaganda and self-radicalized individuals, increasing the likelihood of opportunistic or commemorative attacks rather than coordinated mass-casualty plots. Such incidents are more likely to target high-visibility public spaces, transportation systems, and religious or symbolic sites, reflecting patterns seen throughout 2025. These locations combine accessibility with psychological impact, making them attractive to perpetrators seeking attention, disruption, or symbolic resonance.
At the same time, terrorism in 2026 is unlikely to be driven exclusively by foreign-inspired jihadist ideology. Domestic forms of extremism—encompassing anti-government sentiment, sectarian hatred, political polarization, and grievance-based radicalization—are expected to remain prominent and increasingly intertwined with global narratives. This ideological hybridity complicates threat detection and challenges traditional counterterrorism frameworks that distinguish sharply between domestic and international terrorism. Tactically, attackers are likely to continue favoring low-barrier methods such as vehicle ramming, stabbings, arson, improvised incendiary devices, and small arms, which require minimal planning and are difficult to interdict in advance. While these tactics may limit the scale of individual attacks, their cumulative effect can generate sustained public anxiety and strain security resources, particularly when incidents occur in everyday environments.
In response, Western governments are expected to maintain elevated security postures throughout 2026, particularly around anniversaries, major public events, and sensitive political or religious gatherings. Enhanced monitoring and preventive measures may further constrain organized plots but may also create an environment in which attackers act more spontaneously and unpredictably. To conclude, the terrorism threat facing the United States, Europe, and Australia in 2026 is best understood not as a resurgence of large-scale coordinated campaigns, but as an enduring pattern of decentralized, low-intensity violence capable of producing outsized psychological and political effects.
