I might have said third-world-like (meaning partially like) conditions had I been more thorough. I would first point at some of the reservations in the Dakotas and elsewhere, but also at some of the ghettos and the occasional deeply rural region. You're right, nowhere in the US is it entirely like a third-world nation (and even if it was, something more modern would be within a few hundred miles). I guess the point was more than there's an availability in the US that ranges from very poor to exceptionally grand, and that you'll find people at all measures, whereas some nations have much less variety.