(Wall Street Journal) — There’s a new driver grabbing the wheel in the Motor City. He’s not an elected official, or a local business titan. He’s not even a Detroiter. He’s Rip Rapson, president of the $3.1 billion Kresge Foundation, and his combination of ambition, political connections and financial resources has made him a powerful force in the effort to remake a city much of the country wrote off a generation ago. Under Mr. Rapson’s watch, Kresge has invested more than $100 million in Detroit’s transformation, funding a riverfront promenade, building greenways and backing incentives for entrepreneurs. And he’s just getting started. “Philanthropy has emerged as the sector best able to provide the long-term vision and shorter-term investment of capital the city needs to right itself,” Mr. Rapson said at a private gathering of urban experts in Detroit this spring.