So different yet so alike? Political collective narcissism predicts blatant dehumanization of political outgroups among conservatives and liberals

Previous research found that political polarization goes hand in hand with being strongly identified with a political ingroup. In this research, we assumed this should be the case only among those who identify with their political ingroup in a narcissistic way (stemming from frustrated needs and predicting outgroup hostility). This hypothesis was tested in one experimental (Study 4, n = 525) and three cross-sectional (Study 1, n = 320; Study 2, n = 316; Study 3, n = 500) studies conducted among American and Polish participants. In all studies, we found a consistent positive link between political narcissism, but not political identification, and the blatant dehumanization of political outgroups. This relationship held over and above metadehumanization, measured in Studies 2 and 3. In Studies 3 and 4, we additionally found that political narcissism may also predict aggressive inclinations towards political outgroups, measured with the voodoo doll task. These findings suggest that differentiation between political narcissism and political identification may help to better understand the psychological underpinnings of political polarization.