The American economy is booming, with record growth and record job creation. But global economic pressures mean that some jobs are downsized and some jobs disappear - while others make fortunes. After travelling by train with a primary health care team across one of South Africa's poorest provinces last week, Life this week visits Philadelphia, the capital of Pennsylvania, where the Declaration of Independence was once signed, to look at how the global economy is destroying some traditional employment while making others rich.