Missile threats facing both the United States and its allies in the Asia-Pacific are increasing in complexity, number, and source. In response, the Trump administration is using missile defenses to boost military capability and signal resolve, as indicated by the deployment of THAAD to South Korea. The object of such efforts is not the implausible task of intercepting every threat missile, but building an integrated defense for robust protection against North Korea and a limited capability against China is both feasible and affordable. Such a strategy would reduce the coercive leverage of both states in regional conflicts and enable effective military operations should conflict break out.
A more flexible and adaptable missile defense architecture is essential. The principle of adaptability for the missile defenses is nothing new. Each recent administration has emphasized that missile defense will not have a fixed or final architecture, but will rather evolve through incremental, block, or phased development. The Asia-Pacific has not, however, received the focus it deserves. Although the Obama administration laid out phases for European missile defense efforts, for instance, no comparable set of milestones has been articulated for other regions. This patchwork approach should be articulated and pursued in a more systematic way for the Asia-Pacific region.
Two factors drive this need. First, as missile threats in the region grow, the demand for missile defense assets continues to outstrip supply among both the United States and its allies. These trends indicate a need to posture limited U.S. missile defense assets in a deliberate manner to ensure maximum effectiveness. Second, tight and relatively flat defense budgets points to an increasing need for cooperation among allies and burden-sharing. Greater coordination by the United States with its regional allies—including Japan, South Korea, Australia, Taiwan, and others—could be a basis for improving missile defense well beyond current capabilities.
Articulating a new approach to missile defense in the Asia-Pacific, complete with a concrete set of milestones or goals, could be one useful means to unify several partner nations and better leverage existing tools and capabilities. The path forward will almost certainly include an assessment of the current means available, increasing partner and U.S. missile defense capacity, increasing cooperation, better integrating homeland and regional missile defense efforts, and exploring new technological possibilities.