A few weeks ago I gave a talk on the state of the economy to a group of college students -- almost all Barack Obama enthusiasts -- who were griping about how downright awful things are in America today. As they sipped their Starbucks lattes and adjusted their designer sunglasses, they recited their grievances: The country is awash in debt "that we will have to pay off"; the middle class in shrinking; the polar ice caps are melting; and college is too expensive.

I've been speaking to groups like this one for more than 20 years,...