Ferguson is an example of suburban communities that have seen racial change in recent years. But they are not large in numbers, and incidents of this sort are happily rare. Census data make it clear that, unlike the 1960s, black Americans are able to move to suburbs when they wish, and there's not much evidence that suburban police departments treat them unfairly.
In contrast, Detroit in 1967 was the nation's fifth-largest city, and most other major cities had experienced similarly huge influxes of blacks over the previous generation. The frictions unfortunately generated by this enormous demographic change were of national significance.
There is another difference between then and now. The late 1960s saw a vast increase in violent crime in cities across the nation, to high levels that continued until the 1990s, when New York Mayor Rudolph Giuliani and his police commissioners adopted neighborhood policing tactics that cut crime rates enormously.
Similar policies were adopted elsewhere, with great success. As a result, we live in an America with vastly lower crime rates today.
The Ferguson rioting has already gone on longer than in Detroit in 1967 or Los Angeles in 1992. In both those cases, violence ended shortly after more than 10,000 National Guard and federal troops were sent in.
Missouri Gov. Jay Nixon has not, at this writing, asked for federal troops. President Obama has promised to dispatch Attorney Gen. Eric Holder.
Nixon has called for the "vigorous prosecution" of Wilson. That sounds, as liberal blogger Josh Marshall has noted, like prejudgment of a case about which the facts still seem unclear.
Many Americans seem to have an urge to re-experience the 1960s. But the numbers don't fit. Ferguson is tiny compared to Detroit. The peak U.S. troop strength in Vietnam (536,000) was nearly three times the peak in the last decade in Iraq and Afghanistan (188,000).
Our problems today may seem daunting. But things were much worse in the 1960s.