> What, precisely, do you believe poor Americans are suffering from? The only concrete answer I usually hear is envy (I.e. "oh noes the inequality").

Even if that was the only thing and the only source of suffering for poor Americans was relative deprivation compared to others in their immediate context, so what? Relative deprivation is an important, extensively empirically demonstrated, source of disutility. If one is interested in alleviating actual human suffering that exists, rather than artificially creating self-justifying excuses to defend perpetuating suffering, one would recognize that it is an important problem (not necessarily something which we should blindly bear every cost to minimize, as doing so may at some point do more to exacerbate other sources of suffering than it does to alleviate the suffering directly attributable to relative deprivation, but likewise something that should be considered, weighed, and addressed to the extent practical without doing more harm than good.)