The Quite Rational Basis for North Korea's Japan Overfly

This week, North Korea launched a missile designed to carry what it has described as a “large-sized, heavy nuclear warhead” over Japan. Following the launch, North Korea made clear its intentions for future tests. Kim Jong Un called for “more ballistic rocket launching drills with the Pacific as a target,” according to a paraphrase of his order by North Korean state-run media. That’s an important first, and represents North Korea’s single-most provocative ballistic missile test since it began testing its first-generation Scuds in the 1980s.

For observers of North Korea’s ballistic-missile program, the spate of long-range missile system tests over the past 30 months comes as no surprise. If there was a surprise, it’s the rate at which Pyongyang has been crossing various technical milestones. Over a matter of months, North Korea has shown off new high-performance missiles that will eventually form the core of its burgeoning nuclear forces—Kim Jong Un’s ultimate insurance policy against the fate of Saddam Hussein and Muammar Qaddafi.

Every North Korean ballistic missile test is provocative and illegal. The overfly was certainly both, but for North Korea, it was about far more than theatrical provocation. Launches like the one of this week are set to become more common because they both provide North Korea with key technical information about its deterrent, and serve an important strategic purpose in improving its position should it ever end up at the negotiating table with the United States.

This recent overflight of Japan wasn’t North Korea’s first: In 1998, 2009, 2012, and 2016, North Korea overflew its territory with projectiles. None were designed to serve as strategic nuclear-delivery systems; all were satellite-launch vehicles, designed to deliver payloads into low-earth orbit and not reenter the atmosphere. Some analysts had long worried that the underlying technologies of these vehicles would eventually form the basis of an ICBM, but the large and unwieldy designs Pyongyang showed off had major shortcomings. For one, none of those designs would allow for the kind of  mobility that North Korea’s much smaller KN17 and KN20 systems enjoy. (Without mobility, the missiles would be sitting ducks at fixed launch sites during wartime—an invitation to preemption by the United States.)

Nonetheless, the first of those launches in 1998 was regarded as an exceptional provocation, giving Japan a glimpse of a terrifying future in which North Korean missile overflies could become a fact of life. The launch sparked Japan’s ongoing interest in ballistic-missile defense, spurring investments in sea-based interceptors like the Standard Missile-3 Aegis interceptors and the Patriot Advanced Capability-3 system as a hedge against that possible future. (Only the former has the capability to intercept a missile like the one North Korea just flew over Japan, and only under particular conditions.)

As of this week, Japan’s terrifying future has merged with its present. Even as a clearly agitated Japanese Prime Minister Shinzo Abe reacted to North Korea’s launch on Tuesday morning, saying that his country would take “all possible measures” to ensure the safety of its people, he no doubt knew what lay ahead for Japan.

Earlier this year, Japan began ballistic-missile-attack evacuation drills for its citizens living near likely North Korean target areas. The Japanese government is also seeking earmarked funds in its 2018 budget request for new ballistic missile defense systems. Tokyo may also look to acquire the Terminal High Altitude Area Defense system—the defensive system that has been at the center of domestic and international controversy in South Korea—though this may be less cost effective. Finally, the inexorable growth of the North Korean threat toward Japan may well accelerate plans in Abe's right-wing Liberal Democratic Party to revise the country’s pacifist constitution, allowing Tokyo to formally wield precision-strike weapons for potential use against North Korea.

Even as Tokyo reckons with the arrival of its long-feared nightmare, it’s important to recognize that there are important reasons for Pyongyang—which remains rational despite the metronymic exhortations of many analysts to the contrary—to continue to overfly Japan with its missiles.

On a technical level, a ballistic missile flown at the kind of trajectory North Korea demonstrated this week experiences physical and temperature stresses more in line with what it would see during operational use. North Korea's “lofted” tests, which fly the missile to immense altitudes, keeping its range contained to the Sea of Japan, provide some useful data in this regard. However, a launch like this week’s gives North Korean scientists a chance to observe how the missile may perform in a real attack. (There are outstanding questions, though, about how North Korea would have gathered telemetry data from this missile in the northern Pacific Ocean, where it is thought to have splashed down.)

On a strategic level, Pyongyang hopes that these kinds of tests get Japan and South Korea to question the utility of their respective alliances with the United States. North Korea made clear it undertook this launch because Washington ignored its previous overture—yes, the Guam saga was actually an invitation to negotiations—and carried on with the Ulchi-Freedom Guardian exercise with South Korea.

Pyongyang didn’t mention Japan’s recent military drills with the United States, curiously enough. The implication was clear anyway: Tokyo is facing adverse security outcomes because of activities the United States is carrying out with South Korea. North Korea’s new long-range missiles allow it to make the stakes very real for Japan, and it may hope to drive a wedge between it and the United States.

In this case, the technology and strategy work together to rattle America’s allies’ confidence in Washington’s security commitments in Northeast Asia—the cornerstone of what Pyongyang calls its “hostile policy” in East Asia. This is precisely why U.S. Secretary of State Rex Tillerson released a rare readout of a post-launch phone call with his South Korean and Japanese counterparts, emphasizing that the alliances remained “ironclad” despite North Korean provocations.

What will be difficult for the United States, Japan, and South Korea to accept, however, is that Kim Jong Un will likely get away with continued launches over Japan. Missile defense, while enticing, is at best imperfect, with the costs of a swing-and-a-miss potentially too great. Sanctions—the default answer to new and greater provocations from Pyongyang—have failed to stall Kim. He introduced his current generation of long-range missiles based on advanced composite materials and, most likely, engines manufactured at home despite an extensive international sanctions regime. (China’s imperfect implementation and enforcement of existing sanctions is unlikely to change anytime soon.)

What choices does that leave? Well, there is the military option—part of what's currently “on the table,” as several U.S. officials, including most recently President Donald J. Trump, remind us. Based on the capabilities North Korea has already demonstrated, however, the risks of preemptive military action against Kim Jong Un are unacceptably high. (Again: that’s why Kim has his nukes in the first place.)

With none of these options providing a compelling way out, North Korea will continue testing its missiles—seeking to credibly demonstrate that it deters the United States. Its state media described this week's launch as a “prelude to containing Guam.” With each launch, Pyongyang, however, has left a way out: it wants to talk to the United States.

As difficult as it is for Washington to acknowledge the reality of North Korea’s capabilities, Kim knows that it's precisely his new nuclear-tipped missiles that give him the ability to bargain coercively with mighty America. Just recently, Tillerson and U.S. Defense Secretary James Mattis modified Washington’s precondition for talks with North Korea from a bona fide gesture toward denuclearization—now an outmoded pipe dream—to just “the immediate cessation” of its weapons tests.

Yes, North Korea has a long and unpalatable list of demands of the United States and its allies. And no, Washington should not capitulate or offer unlimited concessions for what may ultimately be unreliable and duplicitous assurances from Kim Jong Un. But as long as North Korea sees no reciprocal interest in Washington, it will keep testing bigger, better, and more powerful missiles at longer and longer ranges.

The unfortunate consequence of this is that if U.S. policymakers decide that there is no good reason to even enter noncommittal exploratory talks with North Korea under their terms, the alternative will be to accept uncapped North Korean technical progress on its increasingly impressive nuclear forces. That shouldn’t be acceptable and that’s why talks are the only realistic option on the table and the least bad out of the alternatives.