The US loves to announce that it is fighting in a "war" on some abstract concept, and subsequently that it has won the war for whichever side it decided it was fighting on - and meanwhile the abstract concept remains unchanged.
In practical terms, the US likes two measures, an international measure which doesn't adjust for local costs, so it can say hey, our people could buy enough food and so on in Cairo, so that's not poverty - ignoring the fact that they're not in Cairo and must pay US prices instead; and a US measure developed in the 20th century which assumes poor people don't need telephones, refrigerators, and such "luxuries" only available to the wealthy a hundred years ago.
In any case, most of the time the people who claim that the war on poverty hasn't been won, like to look at the pre-tax, pre-redistribution income. Ignoring the great impact of the very programmes they are meaning to defend.
See https://www.cbo.gov/publication/61157 for more than you'd ever wanted to know.
Working conditions are by and large also pretty good. Americans love going to work much more than most Europeans.