As Donald Trump and Kim Jong Un continue to hurl insults across the broad Pacific, military planners need to be exploring innovative answers for dealing with the rising threat from North Korea.
At the heart of the problem is the ability of Kim's regime to launch intercontinental ballistic missiles perhaps as far as 8,000 miles as demonstrated by the latest launch of the Kwasong 15 missile.
Even as the range of the North Korean missiles continues to expand, the nuclear weapon program grows as well. We should expect another nuclear test soon -- probably after the holidays -- which may well include an "over ocean, above surface" test of a hydrogen bomb. Meanwhile the rhetoric continues to ramp up from the name-calling (Trump a "dotard" and Kim the "little Rocket Man") to actual threats of war from both sides.
Certainly the first order solution remains diplomacy, despite intermittent dismissal of negotiations by both Trump and Kim. Much of the focus, as it should be, is on getting China to lean in aggressively in a new round of sanctions, hopefully including cutting off or greatly reducing the flow of oil. Hopefully, over time, this will lead to the bargaining table with a return to four-party talks, among the U.S., China, South Korea and Pyongyang. But hope is not a strategy, and in the meantime military planners should be exploring new ideas to curtail the threat from the growing missile program. What can be done?
Improved missile defense: We must build stronger, more reliable, integrated, and fully-deployed system of missile defenses. At the moment, the missile defenses in place are not tactically or strategically connected. Big intercontinental missiles are vulnerable throughout much of their flight, and we have invested heavily in the ability to shoot down the missiles in the so-called "terminal phase," when they are falling down out of the sky at the end of the flight. Those terminal defenses -- the AEGIS missile defense system on ships, the Patriot PAC3, and the Terminal High Altitude Area Defense System (THAAD) on land -- have a relatively high success rate, often approaching 90%. But we need more of them from South Korea, to Japan, to Guam and on to Hawaii.
Additionally, during the "midcourse phase," when the missile is transiting between launch and hitting its target, the intercontinental ballistic missiles are vulnerable to Ground Based Interceptor missiles, currently deployed in Alaska and California. But we do not have enough of them, nor are they part of an integrated defense system, and worst of all their success rate hovers around 50% --- not good enough if you are protecting a city of millions of people. So we should likewise allocate more resources to this part of the problem.
The truly innovative idea would be to go after the missiles as they are launched in what is generally called the "boost phase." This is a difficult shot, but there are new solutions emerging that would use airborne sensors off the coast deployed on drones, kept in place for prolonged periods, and possibly equipped with either missiles or lasers. This "boost phase" solution shows significant promise, although technically demanding, and should be more aggressively pursued.
Cyber tools: Clearly building better missile defenses is necessary but hardly sufficient. It will be necessary to think more aggressively and creatively about using offensive cyber options. The U.S. has enormous ability to attack in cyberspace, but we have typically avoided doing so for two reasons. First, it is considered highly escalatory; and second because the more you use offensive cyber tools the more an opponent can see them and counter them.
North Korea is also largely insulated from the web, and therefore getting a cyber tool into their networks would be difficult and might require covert physical activity on the ground -- quite risky. But clearly the threat is growing rapidly and it may be time to explore a more aggressive posture. One associated benefit of using these cyber tools offensively would be to undermine North Korean confidence in their systems, perhaps leading to punishment and execution of their scientists in the face of "unexplained" failures. It would also reduce the ability of Kim to sell his weapons systems globally by sowing doubt in the marketplace.
Maritime blockade: Throughout my career as a Naval Officer, I participated in a variety of arms embargoes and maritime interception operations, from Haiti to the Balkans and the Persian Gulf. While slow to take effect, and requiring cooperation from regional neighbors (the difficulty here, of course, would be China and Russia) they are largely non-violent and over time can produce real changes in behavior. They could also cut down significantly on both imports and exports, further choking the North Korean economy.
The best case, naturally, would be to use the United Nations Security Council Sanctions process to obtain a formal resolution for a blockade as was done most recently off Libya during the conflict there in 2011. While not in the cards politically at the moment, the next nuclear test -- especially if it is indeed over the ocean -- may finally persuade China to permit such a move. It would required a significant number of warships -- dozens -- but could be conducted by an international coalition. Global navies have significant experience with this type of operation.
Overall, we want diplomacy to work. The best way to get there is to create more pressure on Kim Jong Un, hopefully with Chinese assistance. But we need more creative military options at work, and the package of improved and integrated missile defense, more use of offensive cyber, and a maritime interception operation should be part of it.
James Stavridis, a retired four-star U.S. Navy admiral, was the 16th supreme allied commander at NATO and spent over half of his career in the Pacific Fleet. He is dean of The Fletcher School of Law and Diplomacy at Tufts University.