PINE RIDGE, South Dakota — Alan Jealous, a 27-year-old construction worker, dreamt of building and owning a home. Homeownership is the cornerstone of the American Dream. But for this citizen of the Oglala Lakota Nation living on the Pine Ridge reservation, a community that regularly tops the list of the poorest places in the country, having realized this dream is a monumental achievement. Pine Ridge, a 3,500-square-mile landmass home to nearly 20,000 people, mostly Oglala, has one of the worst economies and some of the weakest infrastructure in the developed world.