Sweden has historically been ethnically close to homogeneous (until the 20th century, life in Scandinavia was hard, and few wanted to move there) and has a relatively flat social hierarchy, meaning that redistributive taxation to fund services is popular (after all, if everyone needs a specific service, having the government provide it through taxes is an economy of scale). America, meanwhile, was founded on racial slavery, which resulted in a racial hierarchy (i.e., the definition of who counts as “white” shifting over time), and there’s a non-negligible proportion of voters who would resent being taxed extra to help lift those below them in this hierarchy closer to their level.