Identity fusion

Identity fusion, a psychological construct rooted in social psychology and cognitive anthropology, is a form of alignment with groups in which members experience a visceral sense of oneness with the group. The construct relies on a distinction between the personal self (characteristics that make someone a unique person, such as height, age, or personality) and the social self (characteristics that align the person with various groups, such as common nationalities, interests, or motivations). As the name suggests, identity fusion involves the union of the personal and social selves. When fusion occurs, both the personal and social selves remain salient and influential but the boundaries between them become highly permeable. In addition, the theory proposes that fused persons come to regard other group members as "family" and develop strong relational ties to them as well as ties to the collective. Therefore, fused persons are not just bound to the collective; they are tied to the individual members of the collective.

The potency of the personal self and relational ties distinguish identity fusion from other forms of alignment with groups, such as "group identification", in which allegiance to the collective eclipses the personal self and relational ties to other group members. Because of this, the personal self and relational ties are not as involved in theories of group identification. Identity fusion theorizes that fusion measures should be more predictive of extreme pro-group behavior than previously proposed measures of identification. In fact, there is growing evidence of this. Measures of identity fusion are particularly powerful predictors of personally costly pro-group behaviors, including endorsement of extreme behaviors, such as fighting and dying for the group.^{[1][2][3][4][5][6][7][8][9][10][11]}