Life has been good to Mervyn L. and Joyce Alphonso: four healthy children, a six-bedroom house, a Mercedes in the driveway. But a few decades ago, life was much bleaker. They were both surviving day to day in Guyana, their families crowded into small cottages without indoor plumbing. Mervyn's father had died when he was 13, casting the youngster into the work force as a messenger who also attended school; Joyce studied furiously in the hopes of getting a job abroad.
Emigration was the only way out--Mervyn left for the States and worked in hospital maintenance before joining a bank, while...