Amy Chua, the “Tiger Mother” who launched a thousand panic attacks among ambitious but lenient parents, is back with an almost-great book about why some groups achieve spectacular success in America while others languish. Written with her husband Jed Rubenfeld (both are law professors at Yale), The Triple Package examines a number of groups who’ve succeeded in this country and advances a thesis about why groups (and nations) prosper or decline.

The success of Asian-American immigrants (this principally includes people from China, Japan, Korea and India) is legendary. Less familiar is the bounding achievement of Nigerian immigrants. Though they account for only 0.7 percent of the black American population, they comprised nearly 25 percent of the blacks at Harvard Business School last year. Nigerian immigrants are estimated to be 10 percent of America’s black physicians. The average family income of Nigerian immigrants is not only above the black average, but above the national average as well.