the us is not a homogeneous high trust society. i get your point though. a welfare system is always liable to abuse. that's the same with most distribution systems we have. for one, there are many ways to evade your taxes. look at sweden. it used to be a homogeneous high trust society, and the welfare system worked fine. it is failing now, and it's not the welfare system that changed. it's beside the point, but i think a lot of socialists and leftists tend to look at the nordic countries as a benchmark for what western societies could achieve. i think they got it backwards. it wasn't our policies that got us there, it was our lack of diversity (among other things of course). now that our prerequisites have changed, so has the outcome.
Sweden