Officially the companies assessed these risks

Initially, it was a very small shock. A few tens of billions of dollars lost in loans to American poor to buy their house. Even though dozens have become hundreds, it was that of a large drop of water across the United States, and more of the planet. But finally limited losses are at the origin of the financial crash of the century. It is a true mystery. Of course, the risk has been disseminated into funds Australian or local German banks by the development of financial techniques, starting with the famous securitization, where individual loans are aggregated in financial securities then resold in small increments with an attractive interest rate. But this dissemination of risk is not sufficient to explain the disaster.

Economists begin to dissect the mechanics of the drama. Hyun Song Shin, a professor at the American University of Princeton (whose works are supported by the Bank of France Foundation), shows the critical role of the interdependence of banks (1). In the hyperfluide financial world in recent years, where institutions ceased to share money, collective mistrust for a single player is enough to fail the system. An economist from Princeton, Markus Brunnermeier, shows that "financial institutions have an individual incentive too play the effect of leverage, excessive imbalances in maturities of their assets, and be too interconnected" (1).

What cracked, it is the network. But we live more and more networking. Other cracks could be heard. He immediately comes to mind: Internet. If the global electronic network fell in Harbour tomorrow, the world economy would quickly become petrified. More way to find references to write the next column to download the latest hilarious video, but also impossible for traders place their orders, for the industry to manage their production chain. However the breakdown of three cables in the Mediterranean was enough to slow down the exchange of data between Europe and Asia last month. And the rise of traffic, with the downloading of films, could blow up the network. However, experts are divided on the reality of this risk. Of course, great failure remains may be possible, and heavy investments are probably necessary to avoid it. But the Web was built to avoid failures. It was even the original purpose of the system developed initially by the military: a network resistant to shocks. When a wire breaks in this spider's Web, information is automatically diverted to the other sons.

Another less visible but also essential network may, him, be much more vulnerable. It is linking business, have become very dependent of each other. Over the past two decades, the industrial giants broke their chain of production. Both in the four corners of the world and through a network of subcontractors. In doing so, they made two implicit assumptions: the borders have disappeared and large suppliers are eternal. These two hypotheses could be swept away by the crisis. No company is immortal. And protectionist pressures may rise in the coming months. The closure of some border may be sufficient to disrupt in depth of swathes of the global industry. History of such examples. During the war of 1914-1918, the production of artillery shells at France was interrupted following the judgment of deliveries of powder by German industry!

Today, the climate is fortunately more peaceful, but supply chains rely on massive international exchanges. Officially, the companies assessed these risks. They have mastered their channels. In reality, the "long market chain" mentioned by the historian Fernand Braudel became so long that they are opaque. The interdependence of companies is underestimated. It may be that modern industry is as vulnerable as the modern finance network.