This qualitative study explored and compared factors that drive individuals with and without military experience to commit violent acts of terrorism within a sample of 10 jihadism-inspired lone actors. Findings reveal four major themes driving violent terrorist action among lone actors: Action, Grievance, Growing in Jihad, Religious Fervor. Results also provide some of the first evidence that drivers of lone actor terrorism differ between those with and without military experience. Factors related to action, certain grievances, and growth in Jihad were seen more commonly among the military-affiliated lone actors than their civilian peers. Implications for policy and prevention are discussed.