One Chicagoan who supports stop and frisk is the father of Hadiya Pendleton, the 15-year-old girl shot down a week after singing at Barack Obama's second inauguration. "If it's already working, why take it away?" he told the New York Post. "If that was possible in Chicago, maybe our daughter would be alive."
Chicago and New York both have tough gun control laws. But bad guys can easily get guns in both cities.
The difference, as the New York Daily News's James Warren has pointed out, is that frequent stops and frisks combined with mandatory three-year sentences for illegal possession of a gun mean that bad guys in New York don't take them out on the street much.
Stop and frisk makes effective the otherwise ineffective gun control that Bloomberg so strongly supports.
An extreme case of what happens when a city ends stop and frisk is Detroit. Coleman Young, the city's first black mayor, did so immediately after winning the first of five elections in 1973.
In short order Detroit became America's murder capital. Its population fell from 1.5 million to 1 million between 1970 and 1990. Crime has abated somewhat since the Young years, but the city's population fell to 713,000 in 2010 -- just over half that when Young took office.
People with jobs and families -- first whites, then blacks -- fled to the suburbs or farther afield. Those left were mostly poor, underemployed, in too many cases criminal -- and not taxpayers. As a result, the city government went bankrupt last month.
New York has strengths Detroit always lacked. But it is not impervious to decline. After Mayor John Lindsay ended tough police practices, the city's population fell from 7.9 million in 1970 to 7.1 million in 1980.
Those who decry stop and frisk as racially discriminatory should remember who is hurt most by violent crime -- law-abiding residents of high-crime neighborhoods, most of them black and Hispanic, people like Hadiya Pendleton.