Defense Secretary Leon Panetta delivered a stark warning that the US could soon face a "cyber Pearl Harbor" if the nation doesn't strengthen digital security. NBC's Jim Miklaszewski reports.

Defense Secretary Leon Panetta issued a call to arms against cyber attacks on U.S. targets and said the Pentagon must be prepared to launch preemptive attacks in cyberspace against potential attackers. He warned that a cyber attack by a nation state or terrorists on the U.S. could be America's "cyber Pearl Harbor" and "be just as destructive as the terrorist attack of 9/11."

In a speech before business executives in New York, Panetta revealed that cyber intruders have already gained access to some of America's critical control systems that run chemical, electric and water systems with the intent to "cause panic, destruction and loss of life."

With a current annual budget of $3 billion for cybersecurity, Panetta urged that more needs to be done to create an army of "skilled cyber warriors" to confront the immediate and growing threat. The Defense Department is already hammering out new "rules of engagement" for a potential cyber war.

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Panetta stressed that defending against potentially disastrous cyber attack on America will take a total government and business-wide effort.

Panetta said that before the 9/11 terrorist attacks, warning signs went largely ignored.

"We cannot let that happen again," Panetta warned. "This is a pre-9/11 moment. The attackers are plotting."

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