Empirical research on terrorism has tended to overlook the heterogeneity of the radicalized population, and how, in its heterogeneity, it differs from the general population. This study first asks how radicalized individuals, irrespective of the activities they participated in during their trajectory, differ from the general population. It then divides radicalized individuals into those who use terrorist violence, and those who do not, asking whether the aforementioned distinctions present differently. Using the (Non-) Involvement in Terrorist Violence (NITV) dataset, variables for which general-population comparisons are feasible are presented and contextualized. Compared to the general population, radicalized individuals are disproportionately male, tend to lack perceived political representation, are more likely to be unemployed, have suffered adverse childhood experiences, and have communicated a desire to hurt others. They are also more likely to have violent criminal antecedents. Although radicalized individuals are no more likely to suffer from mental illness than the general population, radicalized individuals who are so afflicted tend to suffer several specific illnesses at slightly above-average rates. If efforts to prevent citizens from becoming extremists, and extremists from turning to terrorist violence, incorporate specific, rather than general, interventions, it is likely that they will produce more robust results.