PRESCOTT - With the North Korean government saying President Barack Obama is "recklessly" accusing their country of the cyberattack on Sony Pictures, the North Korean National Defense Commission is threatening to attack the U.S.

Obama said on Friday that the U.S. would respond "proportionately" to the attack on Sony.

That prompted an angry response from Pyongyang.

"Our toughest counteraction will be boldly taken against the White House, the Pentagon, and the whole U.S, mainland, the cesspool of terrorism, by far surpassing the 'symmetric counteraction' declared by Obama," the commission's Policy Department said in a statement late Sunday.

If Kim Jong-Un is serious, that could be a problem.

"The North Korean government does have a nuclear weapons capability, although there are problems with it's delivery mechanism, it has a chemical warfare capability, a biological warfare capability, and, obviously, a cyberterrorism capability," said Dr. Richard Bloom, a terrorism expert at the Embry-Riddle Aeronautical University Global Studies Department in Prescott.

"It certainly could hurt, if not the continental U.S., certainly U.S. citizens or U.S. interests worldwide," he said.

Bloom pointed out, however, that Pyongyang's statements toward the U.S. are routinely worded in an "extremely extreme manner," which makes it difficult to tell how much credence to give the pronouncement.

If North Korea wanted to undertake a cyberattack intended to do damage to the American people, the target might be the nation's power grid.

A recent test of the country's grid security was not comforting, said Dr. Jon Haass, ERAU's Professor of Cyber Security and Intelligence, with a simulated combined cyber- and real-world attack "resulting in millions of people being out of power ... and it could take days, or in some cases, weeks, to restore power."

Haass said the best thing for a concerned public to do is to be prepared for an outage just as it would if a storm were to knock out electricity.

"Are you prepared to have food for a little while? Are you prepared to have lights? What's your plan for heat?" he asked, noting that "from the point of view of most people, (they) can't distinguish between a natural catastrophe and something that's man-made."

As for government systems, he said, the big ones - Central Intelligence, Department of Defense - have much stronger security.

"They have what's called 'defense in depth' and layers of security," Haass said, "and they also have the manpower to be able to continuously monitor intrusions and impacts on their data and systems."

Ultimately, a cyberattack on the American people as a whole would have serious repercussions for the attackers.

"We know that people have the technology and they have demonstrated its use," he said. "Do they have the wherewithal to go ahead and pull the trigger," knowing it would be considered an act of war, he asked.

Bloom said Sony needs to make the film that triggered all this, "The Interview," available for viewing immediately.

"It has to get out there, because you're just increasing the probability there will be more terrorist threats and potential terrorist attacks in the future if you don't,'" he said.

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