Also no one wants to walk through blighted or a high crime neighborhood. American cities have a lot more diversity than any of the cities you mention with income disparities separating various races and stocks of people. Homogeneity of the populaces involved is a factor often totally and wholly ignored in these comparisons of "walkable and affordable" cities.

Walking through even the ghetto-est part of Belfast may not be the same as walking through the same in Opa-locka, Miami-Dade County, Florida. There are no racial boundaries to overcome in Belfast or Budapest. Not even remotely close to the extent we encounter in America. Like I said this metric should be factored into these conversations.