Human rights law and international law generally have nothing concrete or actionable to offer the fight against US inequality, but the publicity stirred up by the U.N.’s Alston is a good thinghttps://www.theguardian.com/society/2017/dec/15/america-extreme-poverty-un-special-rapporteur …
Not sure in what proportions but these reasons: the incredible ignorance of U.S. Christians; lack of media attention; end-times pre-millenarianism (this last I think is the smallest reason; for most religious people doctrine is the smaller part of their religious experience)