evidence: The homicide rate is particularly alarming in black male teenagers, the CDC reported. Their homicide rate, already high, nearly doubled between 1984 and 1988 and in some areas exceeds the casualty rate among soldiers in Vietnam, Froehlke said. [...] Washington, D.C., is not alone in its soaring homicide rate. FBI crime statistics show that the increase in the homicide rate nationwide has continued at least through mid-1990, with an 8 percent rise in homicides this year. More than a dozen other large U.S. cities -- including New York, Dallas, San Antonio, Phoenix, Memphis, Milwaukee and Boston -- have already marked all-time high homicide totals in 1990. Homicide totals have declined this year in Detroit, Miami, Atlanta and Denver. [...] What caused the upward spiral in the homicide rate is a complicated question, and what to do about it is even more so. But the first step is a recognition of homicide as a public health crisis, experts agreed.