Without new immigrants, many metropolitan areas such as New York, Chicago, Detroit, Pittsburgh and St. Louis would have posted flat or negative population growth in the last year.Perhaps this is why the progressives in power are obsessed with keeping immigrants inbound. Without them, the urban centers that provide their electoral margins would be revealed for the collapsing failures they are.
If American cities were still vibrant - or even just sustaining - they would be attracting and holding populations. As it is now, they're falling into decay. As a result, many who can leave are doing just that, likely hoping to find greener pastures elsewhere.