Despite UN resolutions and international opposition, North Korea test-launched four intermediate range ballistic missiles on Monday that reached within 200 miles of Japan. The test demonstrates not only Pyongyang’s disregard for more sanctions, but also its progress in missile technology. Besides North Korea, Russia, China, and Iran have also devoted resources to acquiring new missiles with improved range, speed, and accuracy. This evolving threat demands an equally, if not more advanced, technical solution. However, an effective one has been elusive.
A key challenge for developing missile defense systems lies in the speed and unpredictability of an offensive missile. The defender must react to the threat without knowing precisely where the launch will come from or where it will go. Therefore, any defense inevitably trades response time for information – the longer the defender waits, the more information there is on where the missile is going, but there is less time to react.
Technical solutions, therefore, are geared at disrupting a missile at three different stages during its flight path.
The first stage, known as the rocket’s boost phase, is the most difficult phase to defend against. While the missile is easy to spot once the engines are lit, it will be at its fastest, and its trajectory—and final target—is most difficult to calculate. There are currently no viable technical defenses for this phase, however lasers mounted on unmanned aerial vehicles (UAVs) or aircraft could offer a potential solution.
The second phase, the midcourse phase, occurs when the missile reaches its highest altitude and begins to slow down. Defensively, this offers the longest response time, but because of the high altitude it requires large, expensive missiles such as the Ground-based Midcourse Defense (GMD) as interceptors.]
The final phase, the terminal phase, is when the missile has reentered the atmosphere. While defensive missiles and radar systems can be cheaper and less powerful at this stage, they have less reaction time. These systems include the Terminal High Altitude Area Defense (THAAD), which will be deployed in South Korea, and Aegis, a ship-based system deployed on U.S. Navy vessels worldwide.
The United States employs several different missile defense systems whose various strengths are meant to complement one another, but they are by no means a perfect solution. At the end of the day, the challenge of missile defense remains with what Raytheon’s Vice President of Missile and Air Defense Mitch Stevison describes as “hitting a bullet with another bullet.”
This immutable fact has prompted a search for technical solutions known as “left of launch,” that is, a solution that stops a missile prior to it ever being launched. The North Korean threat offers another example. Over the weekend, the New York Times published an article describing how the Obama Administration had spent three years attempting to sabotage the North Korean missile program with cyber warfare techniques, which coincided with a drop in the success rate of North Korean missile tests.
While “left of launch” is attractive for adding another defensive layer, it is also cheaper than mid-flight solutions. As of 2013, the GMD program had cost $40.9 billion over ten years according to a Government Accountability Office report. THAAD, a relatively cheaper terminal phase option, costs $1.6 billion per unit.
The high cost of missile interceptors has significantly shaped missile defense technology in recent years. According to a CSIS report, the Missile Defense Agency’s topline budget decreased by 23.4 percent between 2007 and 2016 while the threats have only gotten worse. High cost has guided the MDA and defense contractors to focus on evolution, not revolution, when it comes to missile defense technology.
A prime example is the Standard Missile family, which has been improved upon for 65 years. Unlike most missile defenses that are meant for only one target type, the latest version, the SM-6, can be used against aircraft, missiles, and surface ships. What is important to note, says Stevison, is that “these new missions are added to an existing missile through software upgrades only.”
Tom Karako, the director of CSIS’ Missile Defense Project, concurs with the value of evolving existing technologies. “Incremental and block evolution of the program of record represents the simplest, most reliable, and most cost-effective way to improve the fielded missile defense force,” Karako said, while adding that increased networking capability among existing systems—for example, using the sensors of one system to target for the missile of another system—could also increase the capability of existing systems.
While such approaches add to U.S. defenses, there are simply not enough deployed systems to meet U.S. defense requirements. The U.S. fields fewer GMD, Aegis, and THAAD systems than needed to cover the requests of combatant commanders. New technologies, such as lasers or hypersonic missile defenses, could also expand capabilities, but will require more time and money to perfect. Ultimately, investment in more systems and technologies are needed in order to cover more geographic area and counter more threats.
There is no one-size-fits-all technology for missile defense. While new solutions are maximizing the utility of existing systems, more numerous and more advanced threats require a more robust defense that is multilayered in order to minimize the risks of ballistic missiles.
Will Edwards is an international producer at The Cipher Brief. Follow him on Twitter @_wedwards.