The theory was usually explained, at least to law enforcement groups, as misdemeanors growing up to become felonies. Alternately, expressed as “by all means sweat the small stuff; everything is small stuff.” In its application to New York City under Mayor Rudy Giuliani, the theory attempted to turn around blighted neighborhoods, especially in the South Bronx, that looked like Germany just after its surrender to the Allies in World War II.
The broken window theory is not universally accepted, but I can tell you from experience that if the cops let a sufficient number of misdemeanors slide, the working assumption among would-be criminals is that the police don’t care what they do.
This seems both logical, and, quite possibly, it helped New York City turn its crime rate around. There were many other factors involved, but it seems great good sense to prevent neighborhoods from looking like war zones.
America has lost a preeminent thinker; I forgive him for being a Boston Red Sox fan.
Update: an archive of James Q. Wilson’s contributions to Commentary may be found here.