Attackers could bring down the entire power grid of the United States in just a few moves, according to a report from The Wall Street Journal.

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The report, citing an unreleased federal study, says a blackout could last more than a year.

The United States is divided into three major power networks: Texas, the western half of the U.S. and the eastern half.

Coordinated attacks in those three grids, pictured above, would knock out power to nine of the nation’s 55,000 electric substations. That would be enough to achieve a nationwide blackout.

The substations take in electricity from power plants and send it out to homes and businesses. The map below shows the flow of power out of those plants.

Shepard Smith spoke to former New York Homeland Security Director Mike Balboni about the frightening report.

He said the information and threat has always been out there, but a recent sniper attack at a California power station last April revealed the vulnerability of the network.

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The Federal Energy Regulatory Commission is requiring the industry to come up with plans by June 1st to protect these assets. Critics argue that it could be costly.

Balboni said there needs to be interlocking capabilities that can back up each other if one goes down. “You don’t want to have the cascade affect which is what we had in 2003.”

Smith reported that 90 percent or more of the power grid system was installed before computers existed.

Now that computers have been added to the system, Balboni said that creates a cyber-security threat as well.

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