"This book is a forecast." Over the next three decades, the aging populations in America, Europe, and Japan will begin to threaten our way of life. The ever-increasing pool of retirees will burden relatively diminished workforces, slowing the pace of growth and straining public and private finances. In stark contrast, the emerging economies---India, Brazil, and China prominent among them---enjoy the benefits of large, youthful, and eager workforces,...