One stock, that of Munich Re, a major German re-insurer, fell 13% in the week preceeding the attack, against a general loss in value of 22% in the previous two months.

So where does this leave the global financial system?

In effect, the immediate direct and indirect costs of the attack are already in the $500bn region. If markets continue to slide and the USA retaliates militarily this figure could double to $ 1 trillion, representing 3% of World GDP.
Some financial companies will inevitably never recover from this event, others will be scarred for a very long time.

Julian E. Salt
LPC Centre for Risk Sciences