A tectonic shift is underway along the Lake Chad to Sahel arc. What began as internecine rivalry inside Boko Haram has, over the last two years, produced mobile splinters and localised franchises that are threading operational ties into the wider Sahel insurgency complex. Those connections are neither accidental nor ephemeral. They reflect structural changes in state cooperation, combat power projection, and criminal economies that will shape insecurity across West Africa for the rest of this decade.

The immediate enabling condition is political fragmentation among regional states. Niger’s 2025 withdrawal from the Multinational Joint Task Force has hollowed out a key mechanism for cross‑border coordination against Lake Chad‑based militants and created gaps along transit corridors used by fighters and weapons. National withdrawals and the emergence of the Alliance of Sahel States have realigned where and how states choose to fight, and they have reduced the bandwidth for the kind of synchronized border policing that constrained jihadi diffusion in the last decade.

At the same time, the intra‑Boko Haram contest between the so‑called JAS faction and the Islamic State West Africa Province has produced both centrifugal and centripetal effects. On one hand, factional fighting has forced fighters off traditional islands and forest bases, increasing mobility. On the other hand, the violence has incentivised surviving commanders to seek external partnerships and rear bases beyond northeast Nigeria. Analysts have documented how these fights have changed control dynamics on Lake Chad and created opportunities for smaller groups and commanders to trade manpower, safe haven, and logistics with Sahel actors.

Two tactical patterns are now visible and consequential. The first is the westward diffusion of fighters and facilitators into north‑central and northwestern corridors of Nigeria that abut Niger and Mali. Localised Boko Haram offshoots, and rebranded cells with genealogies traceable to earlier splinters, have been implicated in violent seizures of villages, imposition of taxation, and the co‑option of bandit networks. Field reports and regional studies point to the re‑emergence of Darul Salam variants and of locally named factions such as “Mahmuda” operating in Kwara and neighbouring states. These groups do not always wear a clear transnational franchise label, but their behaviour — territorial control, taxation, and alliance building with criminal actors — mirrors strategies used by Sahel insurgents.

The second pattern is the operational convergence between Islamic State Sahel Province elements and locally rooted jihadi cells inside Nigeria’s borderlands. An ISSP‑linked phenomenon nicknamed “Lakurawa” has been reported in northwestern Nigeria and on the Niger border, creating a corridor that can knit ISSP, ISWAP, and local facilitators together. Those corridors matter strategically because they create rear areas for logistics, recruitment, and illicit trade that underpin sustained insurgent presence far from traditional Lake Chad sanctuaries. The tactical effect is to broaden the geographical theatre of the Boko Haram‑era conflict into the central Sahel mosaic of contest between Islamic State and al‑Qaeda affiliates.

Violence on the ground underscores why these linkages are not hypothetical. Attacks attributed to Lake Chad actors have continued to inflict heavy military and civilian losses in 2025, and cross‑border strikes into Niger and Cameroon have highlighted the ability of splinter elements to strike outside their historical zones of operation. The erosion of joint regional mechanisms and the emergence of new Sahel security architectures will not by themselves create jihadi unity. Rather they create permissive conditions for tactical alliances of convenience across ideological lines, and for criminal entrepreneurs to monetise conflict in new geographies.

What does this mean for the medium and long term? First, the diffusion of Boko Haram offshoots into Sahel borderlands raises the bar for intelligence collection and the need for real‑time cross‑border cooperation. Fragmented or politicised security institutions will struggle to detect and interdict the fast, low‑signature movements used by small splinter cells. Second, the blending of banditry, local grievance militias, and jihadist cadres creates hybrid threats that are harder to degrade with classic kinetic campaigns alone. Military pressure can displace groups rather than defeat their underlying governance and economic drivers. Third, the entry of outside patrons and private military actors into the Sahel theatre increases the risk that local competitions become proxyised and more resilient. Russia’s stated readiness to support the new AES joint force is an example of how external security partnerships change calculus and capability flows in the region.

Policy responses must be calibrated to these new fault lines. At minimum, three strategic priorities should guide external partners and regional governments. Reinforce practical intelligence sharing and joint border management that is operationally insulated from political ruptures. That means pragmatic mechanisms that keep the MNJTF‑style functions alive even when formal political alignments change. Second, integrate security responses with governance and community resilience measures so that deprived frontier communities are not left with the binary choice between predatory insurgents and predatory security forces. Third, scrutinise external military partnerships and private actors for their long‑term effects on local command and control, arms flows, and accountability. Short‑term security gains that come at the cost of durable local capacity will likely accelerate, not slow, the diffusion of violence.

The emergence of a Boko Haram splinter building operational bridges into the Sahel is not a single event. It is a process driven by shifting state behaviour, battlefield dynamics, and the entrepreneurial logic of insurgent survival. Policymakers should treat it as an indicator of broader regional rebalancing that demands sustained, multi‑layered, and cooperative responses. The choice is stark. Ignore these linkages and fragmentation will reconfigure a larger portion of West Africa into overlapping insurgent and criminal zones. Manage them well and there is a chance to stabilise frontier spaces before the next cycle of realignments hardens.