North Korea, the country whose nuclear ambitions have been the fulcrum of global security concerns for more than a decade, may be a threat in more ways than one.
Concerns about Pyongyang's nuclear arsenal have largely revolved around whether the country could eventually launch a warhead at neighboring South Korea, or even the United States itself. Yet the country's recent actions have converged with percolating fears about the U.S.'s antiquated power grid—which a growing number of observers say is vulnerable to asymmetric threats.
The possibility of an electromagnetic pulse (EMP) attack—defined as the detonation of a nuclear device at high altitude that produces an electromagnetic wave that can either damage or destroy electronic systems—has been mooted since at least the Cold War, the Center for Security Policy notes, while solar flares can also trigger the same effect.
Yet its the threat of a malicious attack on the more than 450,000 miles of high voltage transmission lines that comprise the U.S. power lattice that has some experts worried. It has been a generic concern in national security circles for years. However, North Korea's suspected test of a hydrogen bomb in late January—combined with its firing of a rocket just days ago—has fanned new EMP fears among observers who have warned about the issue for some time.
"The technology of building a super EMP weapon is understood and at least by circumstantial evidence…the North Koreans know how to do it," said Henry (Hank) Cooper, a director at the think tank Foundation for Resilient Societies and a former arms control official under Presidents Ronald Reagan and George H.W. Bush.
Recent events suggest the power grid remains a prime target for terrorism, both at home and abroad. Within the last few months, both Israel and Ukraine were hit with crippling hacks against their respective power grids. Separately, a mysterious 2013 sniper attack on a Silicon Valley substation is widely suspected to have been the result of terrorism.
The possibility of a sophisticated attack on the energy grid "is real and needs to be addressed urgently," James Woolsey, chairman of the Foundation for the Defense of Democracies, told CNBC in a 2014 interview. Woolsey is a Democrat who was CIA Director under President Clinton and a Navy official under former President Carter.
Knowledge about the extent of North Korea's arsenal is notoriously opaque, which is one reason why January's nuclear test was met with skepticism by U.S. officials. Cooper, however insisted that "there is no good reason" to dismiss the idea that the totalitarian regime may in fact be prepping an EMP.
Last month's nuclear test "is disputed on the basis of it not creating a big seismic signal…but that's not true," said Cooper, a trained mechanical engineer. Calling it an "essential threat," Cooper argued that a low-yield hydrogen weapon can be used to produce the conditions that can trigger an EMP attack.
Knowledgeable observers warn that that an EMP detonation is more than just abstract theory or science fiction. Late last year, veteran broadcaster Ted Koppel released a book, "Lights Out," in which he warned an attack on the power grid was a legitimate possibility.
The White House released a contingency plan in October for a theoretical electromagnetic space storm that could disrupt the grid. Separately, federal regulators have also cautioned that EMP events are difficult to anticipate, and could "interrupt power to as many as 130 million people in the United States alone, requiring several years to recover."
At a minimum, the U.S. government has tacitly acknowledged the potential of such an attack or incident. Last May, the North American Aerospace Command (NORAD) announced plans to revive its Cheyenne Mountan Complex, an emblem of the country's Cold War posture. In announcing the move at the time, NORAD officials cited the need to defend the country from an EMP attack.
A successful attack could potentially devastate the domestic economy, causing more than $2 trillion in economic damage, according to a "back of the envelope" December 2015 estimate by The Sage Policy Group, a consulting firm.
Vincent DeVito, a former U.S. Assistant Secretary of Energy under President George W. Bush and who is now a law partner at Bowditch & Dewey, told CNBC that on a scale of 1 to 10, he classified the threat posed by an EMP attack as a 7.
"It's all exposed…and it's not just the U.S.," said DeVito. "We're interconnected with Canada and Mexico, so it's really a North America issue."
A 2014 drill by regulators determined that utilities were unprepared for electronic and physical attacks on the power grid, but since then utilities have been more proactive about fortifying their defenses, DeVito said.
"They're motivated to make the investments, just like airlines are to protect their jets. But without a strong government focus and geopolitical policy to address what these potential threats are," the grid remains a target, he said.
Utilities have been proactive about fortifying the grid on their own, DeVito said, but they require concentrated efforts by the government. Congress's EMP Commission, which disbanded in 2008, estimated a plan to protect the grid from attacks could be put together within five years, at a cost $10-20 billion.
"Congress can fund [EMP defenses], but it's all about prioritizing," DeVito said.