So close and yet so far: U.S. Vice President Mike Pence and the sister of the North Korean leader Kim Jong Un watch the opening ceremony.Reuters / Yonhap

The closing ceremony of South Korea’s Winter Olympics marks the end not just of dazzling twizzles, celebrity curlers, and shirtless Tongans, but also of an interlude in the international crisis over North Korea’s nuclear-weapons program. In recent weeks we’ve witnessed North and South Koreans marching and competing together, American Vice President Mike Pence almost literally rubbing elbows with the sister of the North Korean leader Kim Jong Un, and tentative talk of a grand summit between Kim and South Korean President Moon Jae In. The spectacle of the Olympics has obscured several signs that the nuclear crisis will soon resume—and quite possibly accelerate.

Sanctions

While Pence signaled during the Olympics that the Trump administration is willing to meet directly with North Korean officials, he stressed that the United States will not ease economic sanctions until the North takes steps toward dismantling its nuclear arsenal. In fact, the administration is intent on increasing the pressure amid evidence that international sanctions are inflicting serious pain on the Kim government. On Friday, the U.S. Treasury Department sanctioned dozens of ships and shipping companies that it says are helping North Korea evade severe restrictions on trade in fuel and other essential products.

These sanctions are designed to compel North Korea to make concessions on its nuclear program. Yet in the near term, at least, they could make substantive negotiations less likely to take place. Pence, for example, was planning to hold a secret meeting with North Korea’s official delegation as part of his visit to the opening ceremony, in Pyeongchang, but the North Koreans canceled at the last minute. Their reason? Anger about Pence’s announcement of the latest round of sanctions.

Military Exercises

The United States and South Korea suspended joint military exercises during the Olympics, but they plan to reschedule the massive drills for after the Paralympics conclude, in mid-March. While the Americans and South Koreans characterize these exercises as crucial to preparing for North Korean aggression, the North views the training as a rehearsal for invasion. A commentary in North Korea’s state-run Korean Central News Agency this week pointedly argued that North–South dialogue can’t progress so long as U.S.–South Korean drills persist.

Missile and Nuclear Tests

North Korea has a track record of conducting missile tests in the spring, and that might be particularly true this spring as it refines the technology to place a nuclear warhead on a missile that can reach the United States. The Center for Strategic and International Studies has found that U.S.–South Korean military exercises lead to more provocations by the Kim government when North Korea’s relations with America are strained in the weeks preceding the drills. That’s the case now despite the reconciliation between North and South Korea for the Olympics; the U.S. standoff with North Korea is primarily about nuclear weapons, while the overtures between North and South Korea have avoided nuclear issues.

In testimony before the Senate Intelligence Committee earlier this month, Director of National Intelligence Dan Coats said he expected North Korea to conduct more missile tests in the months ahead. He also suggested that additional tests of nuclear weapons could be in the offing, noting that North Korean officials have threatened to take the extremely provocative step of detonating a hydrogen bomb over the Pacific Ocean. (The North Koreans might be tempted to carry out such an atmospheric nuclear test, which hasn’t occurred since the Chinese staged one in 1980, to dispel doubts about their capacity to threaten the U.S. with nuclear weapons.) In December, three months after North Korea’s last nuclear test, the Trump confidant Senator Lindsey Graham told me he thought there was a 70 percent chance of the Trump administration taking military action against North Korea if Kim Jong Un tested another nuclear bomb. Even if the probability is far lower than that, Graham’s estimate speaks to how high the stakes are in every test that moves North Korea closer to a long-range nuclear capability that the Trump administration claims is unacceptable.

A nuclear-armed North Korea poses a “potentially ... existential” danger to the United States and could blackmail America into abandoning its alliance with South Korea, Coats told the Senate. “The decision time is becoming ever closer in terms of how we respond to this.”

As for whether the U.S. can reverse North Korea’s nuclear program through sanctions rather than military force, Coats didn’t sound particularly optimistic. The North “has repeatedly stated that it does not intend to negotiate its nuclear weapons and missiles away,” he noted.

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