“…Policy diffusion is applied across a wide range of topics (Graham et al., 2013; Shipan & Volden, 2012). One central area is social policy, including for example, welfare policy (Collier & Messick, 1975; Karch, 2007; Kemmerling, 2018; Obinger et al., 2013) and social services (Betz & Neff, 2017; Sugiyama, 2008). Other significant thematic areas are morality policy (Godwin & Schroedel, 2000; Mooney & Lee, 1999; Velasco, 2018), health policy (Gilardi et al., 2009; Shipan & Volden, 2012; Weynland, 2019), environmental policy (Arbolino et al., 2018; Kern, 2000; Kern et al., 2007; Matisoff, 2008), energy policy (Aglanu, 2016; Baldwin et al., 2019; Berry et al., 2015; Carley et al., 2017; Matisoff & Edwards, 2014), and climate policy (Bromley‐Trujillo & Poe, 2020; Jordan & Huitema, 2014; Kammerer & Namhata, 2018; Kern et al., 2023).…”