Each has a potentially important bearing on systemic resilience and hence on the social benefits of restrictions. (a)  Modularity  In 1973, Nobel-prizing winning economist Robert Merton showed that the value of a portfolio of options is at least as great as the value of an option on the portfolio. 15 On the face of it, this seems to fly in the face of modern portfolio theory, of which Merton himself was of course one of the key architects. Whatever happened to the benefits of portfolio diversification? The answer can be found in an unlikely source – Al’Qaeda. Although the precise organisational form of Al’Qaeda is not known with certainty, two structural characteristics are clear. First, it operates not as a centralised, integrated organisation but rather as a highly decentralised and loose network of small terrorist cells. Second, as events have shown, Al’Qaeda has exhibited considerable systemic resilience in the face of repeated and on-going attempts to bring about its collapse. These two characteristics are closely connected. A series of decentralised cells, loosely bonded, make infiltration of the entire Al’Qaeda network extremely unlikely. If any one cell is incapacitated, the likelihood of this undermining the operations of other cells is severely reduced. That, of course, is precisely why Al’Qaeda has chosen this organisational form. 15  6  Merton (1973). BIS Review 40/2010  Al’Qaeda is a prime example of modularity and its effects in strengthening systemic resilience.
In this regard, the euro area is seriously lagging behind: equity capital amounted to only 68% of GDP at end-2016, compared with 128% in the United States. And yet, resources are abundant: the excess of savings relative to investment is around EUR 350 billion per year, which is more than 3% of GDP. It is therefore crucial for the euro area’s economy to better steer these savings towards productive investment across borders, notably by shoring up equity which is the key to an innovation economy. Start ups are well aware of this, but our European scale-ups, midcaps and SMEs also need greater access to equity leverage. The insurance sector has a key role to play since it is the largest institutional investor in the euro area, with total assets of close to EUR 7,800 billion in the second quarter of 2017. In practice, what is the way forward? A large part of the solution lies at the European level. The efforts so far are going in the right direction, but work should now be accelerated with what I call a “Financing Union for Investment and Innovation”. This Financing Union is the microeconomic accelerator that we need to make concrete progress towards a genuine Economic Union in the euro area.