North Korean Foreign Minister Ri Yong-ho on Monday threatened to shoot down US warplanes, claiming "the right to shoot down United States strategic bombers even when they are not inside the airspace border of our country." It's one of the most serious threats the North has leveled to date — and it has experts extremely worried.
"This is how war by miscalculation starts," Vipin Narang, a professor at MIT who studies nuclear weapons, tweeted after seeing Ri's comments. "My anxiety level is up sharply today."
The reason for his increased anxiety is clear: The US frequently flies warplanes over the Korean Peninsula. Ri's comments appear to be a direct response to such a flight conducted on Saturday, in which US B-1B bombers flew along the North Korean coast while remaining in international airspace. It was the farthest north of the demilitarized zone between North and South Korea that any US fighter jet or bomber has flown in the 21st century, according to the Pentagon.
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The idea behind these flights is to deter a war, not start one. They're designed to show the North Korean government that the US is willing to use force if it does something provocative, and thus deter the North from trying anything.
But the recent tensions between President Donald Trump and North Korean leader Kim Jong Un seems to be making the North more aggressive, not less. North Korea's foreign minister's comments suggest the country may no longer tolerate this kind of defensive signaling from the US, and may begin treating these flights as aggressive acts of war even if they don't cross into North Korean airspace.
An actual exchange of fire between North Korea and the US — two nuclear-armed powers — is still unlikely, but the fact that it is much more plausible today than it was yesterday is disturbing.
"I would take Ri's words seriously. This is where we are now," Jenny Town, the assistant director of Johns Hopkins's US-Korea Institute, tells me. "I'm not sure how we walk back from this without some serious diplomatic efforts."