The real wealth of nations

Instapundit highlights a study by the World Bank, which attempts to estimate the wealth of nations, combining natural, produced, and intangible capital. Unsurprisingly, to me at least, the largest source of wealth for America and other well-off nations can be traced to our political freedom, a strong legal system, and good education.

However, the study is lacking in one serious aspect. How could it not calculate the contribution of blogs to the wealth of nations?