“…Although other sociological perspectives provide exceptional insight about internal mechanisms of change (e.g., religion, tolerance, gross domestic product, ethnic fractionalization, elites, legislative system), few theorize about external factors, 22 let alone external, normative ones. While some examine how 8 of 16 -KIM democratic citizenship norms (e.g., voter participation, political engagement, civic duty) manifest within individuals' beliefs and behaviors cross-nationally, current explanations are internal (e.g., cultural context, gender, age) (Bolzendahl & Coffé, 2017;Chang, 2016;Coffé & Bolzendahl, 2010;Hooghe & Oser, 2015). Scholars interested in examining the external determinants of citizenship norms could evaluate their diffusion using institutionalism, thus melding these related but currently distinct normative approaches.…”