NORTH KOREA CONDUCTED its sixth nuclear test on Sunday, claiming that it had detonated a hydrogen bomb that was small and light enough to be mounted on an intercontinental ballistic missile. Pyongyang has made such claims before without proof that it actually possesses those advanced capabilities. Sensors in South Korea, China, and the US indicated, though, that whatever the Hermit Kingdom exploded underground on Sunday was more powerful than the atomic weapons the US used during World War II—a benchmark North Korea had not definitively topped before.
The blast comes on the heels of an unsettling ballistic missile test last week, in which North Korea flew a mid-range projectile over northern Japan’s Hokkaido Island. But both recent tests fit into a larger picture over the last three years of North Korea’s increasing determination to become a fully capable nuclear power. The Obama administration, which pursued so-called “strategic patience,” began to see the necessity of stepping up pressure on North Korea to stop this evolution in the final years of the second term. Trouble is, there are limited options for attempting to address tension with North Korea, and while President Donald Trump has thus far largely followed established paths, namely by levying sanctions, his trademark inflammatory language seems to have emboldened Kim Jong-un rather than cowing him into any type of compliance.
“The test looks like it was about 10 times larger than the previous test [in September 2016],” says Abraham Denmark, the director of the Asia Program at the Wilson Center and a former Deputy Assistant Secretary of Defense for East Asia under President Obama. “Scientists will be poring over the data for several days, but it is clear that the explosion was much larger than anything North Korea has tested before. This means that North Korea is one step closer to fielding a credible nuclear capability that threatens all of East Asia and the United States.”
Analysts worked on Sunday to reconcile varied data about the blast and began to draw preliminary conclusions. The explosion occurred at the underground Punggye-ri testing ground in northwest North Korea. The United States Geological Survey detected that the tremor from the blast had a 6.3 magnitude, while the South Korean Defense Ministry sensed a 5.7 magnitude. Even the lower estimate would still indicate an explosion many times more powerful than North Korea’s 2016 tests. USGS and Chinese instruments also picked up a second, magnitude-4.1 tremor, which may have been caused by a structural collapse in the underground facility.
North Korea is known for conducting weapons tests with far-reaching geopolitical implications around its national holidays—and often near US holidays—to create disruption and confusion. So a test over Labor Day weekend in the US, which happens to fall near the anniversary of the North Korean government’s founding, is not altogether surprising. In discussing North Korea’s missile flyover of Japan last week, many US analysts predicted that a sixth nuclear test could be coming in the next few months. Regardless of how inevitable it may have felt, though, North Korea’s actions are firmly in violation of United Nations Security Council resolutions, and leaders from around the world strongly condemned Sunday’s nuclear test.
“North Korea has conducted a major Nuclear Test. Their words and actions continue to be very hostile and dangerous to the United States,” President Trump said in early morning tweets. “North Korea is a rogue nation which has become a great threat and embarrassment to China, which is trying to help but with little success. South Korea is finding, as I have told them, that their talk of appeasement with North Korea will not work, they only understand one thing!”
With limited options for reacting to North Korea, many experts have been in agreement for months that direct and intense in-person negotiations with the reclusive regime are the only viable path forward. Though economic pressure is helpful, an agreed-upon freeze on weapons testing would have been the only way to stop North Korea from gathering the crucial, real-world test data it has collected in recent months, not to mention this past week. “The problem now is they have tested everything they need to test—the only question is reliability,” Lewis says. “Which should not make anybody feel good, because a stockpile of unreliable weapons should be enough to deter us. And so we’re in this very difficult situation where nuclear weapons force us to go talk to the North Koreans, and that’s going to be really embarrassing and hard for [the Administration]. They’re big on the tough talk.”