Andrew Sullivan has recently been blogging about an article that certain progressive cities are progressive because they have fewer African Americans. This is not only preposterous, but it completely ignores the historical perspective of minorities in cities. Take my current hometown of Minneapolis-Saint Paul, particularly Minneapolis. As late as 1970, Minneapolis was 93% white. This is rather astounding. The African American community was concentrated in a couple neighborhoods, and the rest of the city was almost completely white. (Saint Paul, while slightly more diverse, was also rather white.)
Most of the African Americans who moved north in the first half of the 20th century did so during the Great Migration, and where they moved was mainly based on the railroads. Since Chicago was the end of the Illinois Central (and other lines) which reached in to the south, most blacks stayed there (or took interurbans to Milwaukee for a few nickels). Minneapolis's industrial employment during through the war was diverse, if you count Swedes, Norwegians, Finns, Germans and Irish as diversity.
While the other cities mentioned—Austin, Seattle, Portland, Denver—have had different migration patterns, none were on rail lines which led directly back in to the black belt, so they didn't pull from the pool of African American labor in the industrialization of the early 1900s. And, thus, they are generally less diverse—if you look at diversity as purely black-and-white—than some other cities.
However, Minneapolis has changed, dramatically, over the last 40 years. The minority population, at seven percent in 1970, has increased more than fourfold, and now stands at nearly one third. Much of this has been Asian and Hispanic immigration, but a significant portion has been African Americans moving from other cities, especially Chicago. And the adjustment to a more diverse city has not been smooth. In the 1980s and 1990s, Minneapolis saw increased crime, often blamed on imported street gangs and drugs. In the 1990s, the city was nick-named Murderopolis, and saw nearly 100 murders in a year—for a city with fewer than 400,000 residents. And the change has been dramatic; in many http://www.ci.minneapolis.mn.us/neighborhoods/>neighborhoods, (an example from the Minneapolis Neighborhood website) there has been an almost full-scale switch from white to black in 20 years (all taking place after the 1980s—i.e. not done illegally through redlining), a phenomenon David Carr described last year in the Times. (Recent surveys show the racial makeup of the city may be stabilizing.)
In other words, Minneapolis is not a white city without any racial tensions. It's far from it, yet it's continued to be a rather progressive place. (Although some of this can probably be attributed to conservatives fleeing to the suburbs—the same suburbs that spawn creatures like Michele Bachmann. Minneapolis's outer suburbs are very, very red.) But in the last few years, a curious trend has emerged. Crime has been dropping, which is often attributed to more police on the streets and community development. This summer, the city had six murders in the first six months of the year, shocking some local historians. The trend has continued to be low; there have currently been about a dozen murders this year in the city, so it's on place to be at one-sixth the rate of the mid-90s.
In the mean time, the city (along with Saint Paul, which is also rather safe) has welcomed tens of thousands of new immigrants, including many Hmong and Somali refugees. There's no second language in the city—signs and materials are often translated in to Spanish, Hmong and Somali. Renn's contention that these progressive cities are only progressive because of their racial makeup holds no water. In other words, causation does not necessarily imply correlation.