Free market capitalism is far more than economic theory. It is the engine of social mobility -- the highway to the American Dream. It's what makes it possible for a husband and wife to start their own business, or a new immigrant to open a restaurant, or a single mom to go back to college and to build a better career. It is what allowed entrepreneurs in Silicon Valley to change the way the world sells products and searches for information. It's what transformed America from a rugged frontier to the greatest economic power in history -- a nation that gave the world the steamboat and the airplane, the computer and the CAT scan, the Internet and the iPod.