The crisis began when college basketball fans downloaded a free March Madness application to their smart phones. The app hid spyware that stole passwords, intercepted e-mails and created havoc.
Soon 60 million cell phones were dead. The Internet crashed and commerce collapsed. White House aides discussed declaring martial law.
That formed some of the doomsday scenario when 10 former White House advisers and other top officials met Tuesday in a rare public cyber war-game designed to highlight the potential vulnerability of the nation's digital infrastructure to attack.
The results were hardly reassuring.
"We're in uncharted territory here," was the most common refrain during a three-hour simulated crisis meeting of the National Security Council, the crux of the Cyber Shockwave exercise.
The worst-case scenario presented in a Washington hotel ballroom Tuesday would almost certainly overwhelm cyber defenses being proposed in Washington.
It began with the March Madness application, but then an unidentified insider apparently sabotaged the software patch, making the problem -- and the phony news bulletins that played on giant screens -- far worse.
Then for reasons never explained, homemade bombs exploded by electric power stations and gas pipelines in Tennessee and Kentucky. And a monster Category 4 hurricane slammed into the Gulf Coast.
Michael Chertoff, who played the national security adviser in the exercise, had headed the Department of Homeland Security when Hurricane Katrina struck in 2005. "The biggest danger," he declared, "is if we're ineffective."
Panelists brought verisimilitude to their roles.
Stewart Baker, former general counsel of the National Security Agency, said he would urge the White House to shut down cell phone networks even if no law specifically allows it.
"We will be criticized if we don't do everything we can," Baker said. "We can straighten out the (legal) authorities over time."
Francis Fragos Townsend, who served as counterterrorism adviser in the Bush White House, called for rationing of gasoline and other supplies if necessary.
John Negroponte, who spent most of his career as a diplomat before becoming the first director of national intelligence, urged a diplomatic approach.
The group decided to advise the president to federalize the National Guard, even if governors objected, and deploy them -- perhaps backed by the U.S. military -- to guard power lines and prevent unrest.
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