Mark Sparkman is a former senior officer with the CIA's National Clandestine Service, and is now a senior international affairs analyst with the RAND Corporation. He wrote this article: The Real Cyber Threat, for CNN http://www.rand.org/commentary/2013/05/21/CNN.html.
In the article's introduction, Sparkman states: "Plenty of people have been warning us these days to worry about cyber attacks, but generally we have been worrying about the wrong things. Most "cyber Armageddon" scenarios focus on gaps in our physical infrastructure and even far-fetched scenarios such as infant incubators in hospitals being turned off. But major swathes of the United States have routinely gone without electricity and water for days following natural disasters. Soon enough, life gradually gets back to normal. Want real chaos? Destroy confidence in the banking system (or even a part of it), and just stand back and watch...."
What Sparkman said about the electric grid and water is correct - up to a point. If cyber could only cause a several day outage, it would be expensive but not insurmountable. Back-up power supplies would be available and "life would get back to normal". However, the reason cyber is such a threat to the nation (and internationally as well) is that cyber attacks can damage or destroy critical equipment such as transformers, boilers, turbines, etc. These are custom equipment that can take 9-18 months to produce and ship. Moreover, many of these large components are not even made in the US anymore. As a result, a targeted attack against this equipment can cause EXTENDED outages of up to 9-18 MONTHS or more! The other point that Sparkman didn't address is that cyber attacks against critical infrastructures can kill people and cause massive environmental discharges that can last for months or longer.
Yes- banking is important. But so is protecting our critical infrastructures.