I get his point that people originally from the Third World are perhaps more accustomed to personal privation and will have a certain advantage in that regard, but I doubt very much the idea that life will not only go on, but will actually be better, in those areas with a heavy immigrant population. Does Miami's population sustain itself entirely on food and energy produced within a 50 mile radius of the city? Thought not. Remove or disrupt those external links and see what happens.