With the test of a possible hydrogen device, Kim Jung-un has now played his latest and most powerful card. In doing so, he has imparted a greater sense of urgency to the ongoing crisis. But, like the launch of a ballistic missile over Japan and threats of an EMP attack on the United States, this latest move is straight out of Pyongyang's standard playbook and entirely consistent with the now familiar cycle of provocation, crisis, and temporary resolution that has played out repeatedly for over 20 years. While each successive crisis has brought us closer to the brink of armed conflict, neither side has sought to cross the line into war. The costs and risks have been considered too high.



The current Korean crisis could lead to large-scale conflict, especially if Pyongyang carries out its threat to launch missiles close to Guam. Such a reckless move would go beyond brinkmanship. It would probably force the Trump administration to shoot down the incoming missiles, leading to further escalation. If the North then responded with an armed strike against the U.S. and our allies, the president would have few options other than the employment of overwhelming military force. While there are no good military options, war could result from North Korea's miscalculation. It happened before, with Kim's grandfather.



A more likely outcome is that the crisis, perhaps after more missile tests, will end in the same fashion that others have since the emergence of the North's nuclear-weapons program in the early 1990s. The U.S. would once again call for more sanctions and more pressure on China, with the goal of persuading Kim to return to the negotiating table and accept the "denuclearization" of the Peninsula. North Korea would once again declare victory while continuing to expand its nuclear arsenal and developing ever more capable ballistic missiles.

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But this long-established pattern may be coming to an end, with potentially enormous consequences for U.S. security and that of our allies. Just days ago, General Joseph Selva, vice chairman of the Joint Chiefs of Staff, provided what some consider a reassuring assessment of North Korea's missile capabilities, stating that the North "has yet to demonstrate it has the requisite technology and capability to target and strike the United States with a nuclear weapon." Yet Pyongyang may well be on the verge of achieving exactly that capability, perhaps with high-yield warheads on relatively inaccurate missiles.



In July, North Korea conducted two successful tests of ICBM-class missiles. That same month, the Defense Intelligence Agency reportedly assessed that the North has successfully miniaturized a nuclear warhead that can fit in the front end of a ballistic missile. The latest nuclear test moves North Korea ever closer to what it has long sought — the ability to hold American cities hostage to Pyongyang's blackmail demands. When the North does possess nuclear-armed ICBMs able to hold even a small number of American cities at risk, the rules of the game will change. The next crisis will be different.



Possessing the capability to target and strike U.S. cities with nuclear weapons could fundamentally alter Pyongyang's calculations. Today, the stated policy of the Kim regime is the unification of the Peninsula, by force if necessary. But the North appears to understand that, under present circumstances, it would lose an all-out war with the U.S. and its allies. North Korea's conventional forces are outmatched by the American and South Korean forces arrayed against them, which include massive forces that would flow into the theater during a conflict. Even if Pyongyang employed large-scale chemical and biological warfare, which it is almost certainly prepared to do, the overwhelming response by the U.S., perhaps not limited to conventional retaliation, could well mean the elimination of the Kim regime.



The key for North Korea is to change what it calls the "correlation of forces" by deterring the U.S. and others from coming to the assistance of the South, especially by blocking reinforcements based in Japan, Guam, and the U.S. homeland. The means to do this, according to Pyongyang's propaganda machine, is to threaten American and Japanese cities with nuclear destruction. This is the reason the North devotes enormous resources to its nuclear and missile programs — not to deter an attack by the U.S. but to deter the U.S. from coming to the assistance of Seoul when the North moves south.

Washington's national-security establishment has long discounted this thinking as overly risky on the part of Pyongyang, perhaps to the point of irrationality. Common wisdom holds that, if North Korea launches even one nuclear weapon against the U.S., the result will be the complete destruction of the entire country. But from the North's perspective, which is the one that matters most, believing that it can deter the U.S. may be a gamble worth taking — and we know Kim is a gambler. Whether rational or not, if he thinks he can deter the U.S., the likelihood that the next crisis will escalate to armed conflict increases substantially. Many wars have resulted from misunderstandings and miscommunication, and the next Korean crisis may lead to that outcome.



So how can the U.S. best prepare for the next Korean crisis? One way would be for the U.S. to use military force to destroy North Korea's nuclear and missile facilities now — better to end the threat before it metastasizes rather than after. Presidents George W. Bush and Barack Obama both said they would not permit North Korea to have nuclear-armed ICBMs. President Trump stated explicitly that "it won't happen," with the "it" referring to North Korea's achieving an ICBM capability. His repeated references to all options being on the table are meant to suggest that he will use force if necessary to prevent Kim from gaining the capability to destroy American cities.



But deciding in favor of the military option will be challenged on at least three grounds. First, while the U.S. must be prepared to respond with overwhelming force to the use of force by the North, a preemptive attack by the U.S. on a scale necessary to destroy the North's missile and nuclear programs could result in large-scale conflict, with hundreds of thousands if not millions of casualties. Would our allies, particularly South Korea, be willing to go along? Would the U.S. be willing to accept the cost in lives and national treasure?

Second, it will be difficult to determine when to strike. The internal arguments will most certainly favor delay based on the assessment that the North is not yet at the point of deploying an ICBM. There will always be some related technology that the U.S. has not seen tested. Intelligence assessments are understandably conservative and often take months or longer to develop. But if the delay is too long, it will be too late to prevent "it" from happening.

And third, the counterargument to preemption that will inevitably surface will be that the U.S. can effectively deter Pyongyang even if it possesses an ICBM capability. After all, the argument will go, the U.S. for decades successfully deterred the Soviet Union, a much larger threat, which possessed thousands of nuclear warheads pointed at the U.S. homeland. Never mind that the leadership attributes of North Korea are much different from those of the Soviet Union or that the object and dynamics of deterrence in the Cold War were much different from that with Korea.



The decision to employ or not employ preemptive force to eliminate the North's nuclear and missile capabilities will be the president's alone. To improve the circumstances and possibly reduce the need to use force, the U.S. should take the following actions to meet the growing threat:

Stop making counterproductive statements. Reciting talking points from the State Department's Asia Bureau that the U.S. does not want North Korea to be an enemy, or that Pyongyang is showing "restraint" when in fact it is only preparing more missile launches and nuclear tests, projects an image of weakness that only encourages the North to continue its provocations to test U.S. resolve.

Take firm actions to demonstrate both U.S. capability and resolve, including rebuilding U.S.-theater nuclear capabilities to strengthen deterrence and reassure allies. This may include the redeployment of theater weapons to South Korea.

Back the talk of massive funding for missile defenses with both short-term and long-term efforts, including the development and deployment of a layered homeland missile defense with land-, sea-, and space-based interceptors and sensors. The Obama administration reduced the number of ground-based interceptors that were considered necessary to meet the North Korean threat and eliminated programs designed to keep U.S. defenses ahead of that advancing threat. We are now paying the price for that negligence.

Retain denuclearization of the Peninsula as our first-order objective, but stop indulging in the fantasy that more sanctions and more pressure on China will alone produce this desired outcome. The Kim regime will not give up its missiles or nuclear weapons. Under three previous administrations, the U.S. has followed the failed path of negotiations, at times sweetened by the provision of light-water reactors, heavy fuel oil, and other benefits. For 25 years, North Korea has moved forward with its missile and nuclear programs.

The above approach will be decried as the abandonment of diplomacy in favor of the military option. This is particularly the case for those who wrongly equate diplomacy with negotiations and for those who wrongly argue that the only choice is between negotiation and war. In fact, continuing the failed approach of the past will lead not to denuclearization but to conflict, either because the president feels compelled to preempt or because Kim Jung-un believes he can win a war of unification.



What is required is the redirection of diplomacy to achieve denuclearization while reducing the prospect for conflict. To succeed, U.S. diplomacy must be employed as an essential component of a comprehensive strategy to contain North Korea. New avenues need to be pursued through diplomatic channels to sever North Korea's sales of missiles and nuclear materials and to gain international support for actions the U.S. and allies may take, such as shooting down the North's missiles. And yes, diplomacy is essential to push for regime change from within, perhaps by encouraging Chinese intervention to replace the Kim dynasty in Pyongyang or by providing hope and resources to the repressed population of the North.

Commentary by Robert Joseph, a former undersecretary of state for arms control and international security.

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