I find it fascinating how empirical evidence proves that vast mobility exists between levels of prosperity... One might think therefore, given the evidence, that we wouldn't be forever mired in this us-vs-them debate...
Clearly the "us" and the "them" are composed of ever-changing individual combatants... I.e., some of the "us" inevitably become the "them" and vice versa... The question is, in terms of upward mobility, who wants to work for it and who wants government to give it to them?
With respect to poverty, is government the answer, or in fact the problem to begin with?
Here's Milton Friedman on the topic (this is what you call confirmation bias):