Richard Schwartz, a common friend of Mr. Giuliani and the institute, set out to school the once and future candidate on policy. “We had him in,” Mr. Mone says, “and talked about education, talked about welfare reform, talked about crime. We already had been publishing [articles about] Bill Bratton’s work.” As commissioner of the New York City Transit Police, Mr. Bratton had applied “broken windows” principles, enforcing laws against public disorder and thereby reducing serious crime.

In March 1992 the institute held a half-day forum around a special City Journal issue on quality-of-life issues. “Rudy was in the audience, and he was taking notes during the entire conference,” Mr. Mone says. “As he educated himself about the city for the second run,” Mr. Giuliani “became very familiar with our work and started becoming an active consumer of it.” He faced Mr. Dinkins again in 1993, and this time he won. The new mayor appointed Mr. Schwartz senior adviser and Mr. Bratton police commissioner.

Mr. Giuliani’s two-term mayoralty is generally reckoned a success. At the institute, Mr. Mone recalls, it was “mind-boggling”: “You write something, and then it suddenly happens,” he says. “Most of it worked—you could see the city change.” Mr. Bratton and his successors presided over a steep drop in violent crime. Welfare rolls declined from more than a million to fewer than 500,000.

Only in education did the mayor’s reach exceed his grasp.