Human capital, i.e., the skill and knowledge of workers, is the most important ingredient of an economy, and generates 70% of national income in an industrialized country. An analysis of how devastating destruction did not ruin one economy will help prove this contention. In 1995, there occurred a totally unanticipated large-scale earthquake in Kobe, Japan, which resulted in the lossof 6,500 lives and the demolition of 100,000 buildings. Yet, within 15 months, the economy of the city returned to the pre-earthquake level, and soon after, its economy boomed. Destroyed buildings and plants can be rebuilt within a year or so, but it takes more than a decade to train a worker to the necessary level of skill and education required for the modern economy. Since the earthquake did not destroy most of the people in the city, their human capital remained intact, although their physical capital had been severely damaged.

Similarly, on September 11, 2001, two tall buildings of the World Trade Center in New York were completely demolished by terrorist attacks, with more than 6,000 lives lost. However, since the most of human capital of the city remain intact, it is quite possible that the city will return to its economic normalcy within a year or so, if there is the collective will to do so.