such a way that a convergence of social ills creates a nidus in which it can flourish. It is our belief that New York City, special though it may be, exemplifies these conclusions. In New York City, as in the United States, the epidemic is highly localized and is flourishing in social settings where there is a ''synergism of plagues" (Wallace, 1988).
Much of the attention given to the epidemic has focused on national estimates and national needs. Although these are perfectly appropriate concerns, it must be understood that ultimately the epidemic, its impacts, and the responses to the impacts are experienced in specific locales. The United States, unlike many European countries, is composed of states and other political subunits that can and do pursue quasi-independent policies in many aspects of social life. For instance, all states, counties, and most large cities have their own public health agencies, which have differing traditions and varying levels of quality. In addition, these subnational, geopolitical units often have different political, economic, welfare, and crime control practices, all of which are involved in dealing with HIV/AIDS.
Although these subnational jurisdictions are smaller in size and population than the country, they are not homogeneous social and cultural units. Affluent people live in some parts of a city, and poor people live in others; individuals of European descent live in some communities, and African Americans and persons of Latin descent live in others. In some cities there are residential communities of gay men and lesbians, but in many there are not. Because HIV is not spread through casual contact, the structure of social networks in different localities and the geographical mobility of persons engaging in risky behavior shape the transmission of the virus. Sexual relationships and the sharing of drug injection paraphernalia are not random activities, but are embedded in other patterns of social interaction. HIV/AIDS is thus a disease of neighborhoods and communities, of high-prevalence localities and low-prevalence localities. Even a cursory look at the patterns of CDC-defined AIDS cases suggests distinct patterns in different cities. For example, many cities have few intravenous drug users who are infected and hence few women and infants who are HIV positive, while others have many intravenous drug users and so many infected women and infants.
New York has always been described as "special," meaning that it is unlike any other city in the United States. This view has considerable truth in it: New York City is an unruly, chaotic urban place, which regularly seems to verge on being economically and politically unmanageable. Its residents are the children of old immigrants who came by boat and new arrivals just off an airliner. New York City is actually a large number of collaborating and competing communities with disparate levels of power and resources. Many of these communities have no direct contact with other communities and compete with each other over resources and entitlements