North Korea expert says 'global catastrophe' looms Blaine Harden told ABC News he is concerned about the possibility of war.

 -- Blaine Harden spent decades reporting across Africa, Eastern Europe, and Asia, but for the former Washington Post East Asia bureau chief, covering North Korea has been unlike any other assignment.

“It was hard slogging. It still is hard slogging,” Harden told ABC News. “North Korea is, you know, the longest-lasting totalitarian state in the history of the planet. Seventy years almost. And there’s nothing like it.”

Harden has not only visited and reported on the country, he has written three books focused exclusively on nonfiction narratives uncovered through his years of work there. Now, his latest book, “King of Spies,” lays out the largely unknown story of Donald Nichols, an unlikely yet effective American spymaster. Nichols arrived on the Korean peninsula in 1946, carefully constructed an intricate network of spies, and became a brutal “one-man war machine” as a young man in his 20s.

For Harden, examining the barbarism and trauma of the Korean War in which Nichols played such a crucial role held important lessons about the history of U.S.-North Korean relations, particularly after the U.S. began its brutal bombing campaign.

“They destroyed virtually every city, every town in North Korea. General Curtis LeMay who was head of the Strategic Air Command at the time estimated that the Americans killed 20 percent of the civilians in North Korea,” Harden said. “So that bombing was a fact. It’s a historical experience that the grandparents of the current people of North Korea all experienced.”

The Kim family has leveraged that loss of life into a powerful anti-American message to this day, Harden said.

“They perceive the fundamental war, the only war North Korea’s ever fought, to be a different war, one where the Americans and the South Koreans sneakily attacked, and the Kim family brilliantly won,” said Harden.

“It’s almost as if the war ended last Thursday, if it ended at all," the author added. "And now, that fact-based narrative has found some real zip, because of what Donald Trump is saying.”

For all the talk about North Korean leader Kim Jong-Un as unpredictable or unstable, Harden said the regime has been largely consistent over the years.

“They are really consistent, and their track record is they’re getting better at what they do,” said Harden. “The threats, the bloodcurdling rhetoric that you could hear from North Korea, it hasn’t really changed for decades. What’s new and what is confusing to the North Koreans is they’re starting to hear echoes –- reverse echoes -- of that rhetoric from America’s president.”

Amid conflicting statements from President Trump and his cabinet, and headlines about North Korea’s advanced weapons capabilities, even Harden said he is nervous about the possibility of war.

“The behavior of the Trump administration is making it more complicated to implement the least bad solution, which is to talk because [North Korean officials] don’t know who to talk to, whether to believe what they say, because the president can undermine it the next day with a tweet,” said Harden.

“I’m more concerned than I was before. But then you know, it’s the Kim family that’s pushing the nukes and the long-range missiles. That’s not the fault of Donald Trump," Harden added. "They are setting up what could be, you know, a global catastrophe."

Check out the full conversation with Harden on this week’s episode of "Uncomfortable" here.

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