Several studies have shed light on factors that contribute to radicalization. However, fewer studies have addressed the factors that contribute to deradicalization, especially with terrorist detainees as participants. The present study investigates the role of attitudes toward rehabilitation in deradicalization programs, and its role in predicting the outcome for these programs. We hypothesized that when terrorist detainees adopt alternative identities (identities alternative to their jihadist identity), their support for jihad as war will be lessened, even when they still hold jihadist ideology as their source of significance. To test this hypothesis, we obtained 89 interview profiles of actual terrorist detainees across 35 Indonesian prisons. We found that lesser support for jihad as war was predicted by a more positive attitude toward the deradicalization program, and this was mediated by the adoption of alternative identities. Further, the effect of the mediator on support for jihad as war was neither weakened nor strengthened by perceived significance of jihadist ideology. These findings suggest that even when a person possesses a strong ideological commitment to jihad, this may not manifest into violence when they adopt alternative identities and goals. These results were interpreted and discussed through goal systems theory and the multifinality account of radical behavior.