The protracted war against violent extremism provides plausible evidence about the ineffectiveness of purely militaristic approaches. The G-5 Sahel region witnessed an overall trend of mounting insecurity (2001–2017) despite a plethora of programs by multiple actors to defeat terrorism. Deterring rather than defeating terrorism gained momentum in the fourth wave of deterrence research. Contemporary Deterrence Theory (CDT) suggests a toolkit of punishment, denial and delegitimization to face asymmetric threats posed by violent non-state actors. The present article analyzes the US policy instruments and the upward pattern of terrorist attacks in the G5 Sahel states based on the data of global terrorism database (GTD). It also examines the concepts of ungoverned space and state fragility, which represent the bedrock of US intervention in the region. The study argues for a shift of US policy instruments in the Sahel from defeating to deterring terrorism based on the tenets of CDT. Much more attention should be diverted towards a nuanced approach that distinguishes between domestic and transnational extremist groups, and prioritizes robust homegrown delegitimization initiatives in conjunction with more inclusive political processes and socio-economic resilience programs.