This excerpt originally appeared in Bloomberg on April 26, 2012.

One of the best sentences I have read in the last year is by the economist Tyler Cowen.

“We thought we were richer than we were,” he writes in his book “The Great Stagnation.” The elegant simplicity of this statement explains our economic crisis, sweeping in everybody who went overboard -- governments and bankers, homeowners and investors. The world is rich, but not as rich as we all thought it was.

Cowen’s bon mot popped into my mind after the recent announcement by Cristina Fernandez de Kirchner, president of Argentina, that her government will nationalize YPF, the nation’s largest oil company, controlled until now by the Spanish energy conglomerate Repsol YPF SA. (REP)