Ta-Nehisi Coates has a very smart piece on Bill Cosby's latter-day "Come On, People" crusade in the latest issue of the Atlantic Monthly. It will deservedly be a standard reference for years to come.

However, Coates makes one well-intentioned mistake: he thinks people who decry the current state of the poor black community are nostalgicists.

It's an understandable misimpression, typical of many beyond Coates. Sixties ethnographies of black communities like Behind Ghetto Walls about St. Louis, Soulside or Tally's Corner about Washington, D. C., or A Place on the Corner about Chicago show that real life in black communities in the old days was more than what you see in starchy photos of lodge functions. Crime, out-of-wedlock birth, and unemployment were hardly unknown.

However, people often don't take in all of what these books show. The issue is not whether a black person on the Southside of Chicago in 1925 would have been shocked to see a woman raising a child alone. There are studies reminding us that such circumstances were well known to blacks long before 1970. The issue is that today, when 70 percent of black babies are born outside of wedlock, (and in inner cities, typically, the figure is closer to 90 percent), it is almost shocking when a child does have a father.

The difference between then and now is not a matter of either/or, but of degree. Nobody thinks old-time, black culture was a "fount of virtue," as Coates has it. But there is a stark degree difference between what poor black communities were like before the 60s, and since then.

This is not mere historiographical hair-splitting, because the charge that Cosby is indulging in nostalgia has larger implications. Cosby's central point is that what's happening in black America today can't be linked to racism, since racism has been receding since the 60s. He thinks, therefore, that we are faced with a cultural problem.

The objection that old black communities were just like new ones is an attempt to refute that cultural argument. The idea is that black people's problem back in the day was racism (upon which we all agree), and that if black people today are just doing the same stuff their great-grandparents were doing, then the main problem today is racism too.

But if Coates or others were put in a time machine to sample life in a poor black community 80 years ago, they would realize their mistake.

Back to Chicago in 1925, black leaders were worried that the black out-of-wedlock birth rate was 15 percent. Obviously that figure sounds like science fiction today, and it's hard to trace that to racism. Black laborers in Detroit at this same time regularly travelled 90 minutes to the Ford plant; William Julius Wilson documented their equivalents in the 80s dismissing the same distance as requiring them to get up too early. In 1940, 9 in 10 black Indianapolis residents worked full-time. By 1976, tens of thousands of blacks in Indianapolis were on welfare – three times more than had been in 1964 -- and people were regularly turning down wage work.

Life in a St. Louis housing project in the 60s was no fun, and some of the residents' complaints would be familiar to us; they were about trash and people sleeping around. What is significant is what was absent: guns were not common coin, nor was selling drugs. A D.C. ghetto included types who weren't into working: "corner men." However, there were only so many of them.

Today we no longer talk of "corner men" because black men living outside of the legal work arena is no longer unusual. Corner men were usually also winos (remember "Ned the Wino" on Good Times?) not drug addicts stealing for a fix or drug sellers.

Now, the point is not to condemn today's blacks for "misbehavior." There are various explanations for what made the difference between then and now, and none that I consider responsible are about "character." Many point to the disappearance of factory jobs; others see crack as the main problem.

I think the crucial factor was the transformation of Aid to Families with Dependent Children from a temporary safety net to an open-ended program that became a lifestyle, something that happened quietly in the late 60s.

Whatever the cause, the point is that something did happen – and it wasn't that racism got worse (recall that earlier blacks dealt with both overt and "institutional" racism). When old-timers say that around thirty years ago the old heads in black communities lost their authority over teenagers, I think it is uncharitable -- and unempirical -- to dismiss them as wallowing in what Coates calls "a homily to a hazy black past."

As we chart our path, we cannot pretend that we are fighting the same battles our great-grandparents did: i.e. against "white privilege."