Well, if Europe has a major recession, and the financial system in Europe starts spinning out of control, that will have a direct impact on U.S. growth and our ability to create jobs and people raising their living standards.
By comparison, Apple and RIM offer directcontrol over the devices that implement their operating systems and have measures to detect and disable attempts to modify the operating system.
Under a private system, the link between price deviation and correction is immediate and strong because supply is under the directcontrol of the currency issuers, who have the means through loan and trading operations to tightly clamp down on (or expand) the supply.