Even in the best case, nonproliferation initiatives can take years to bear fruit. They also tend to yield something other than complete success. Few things illustrate this point as well as the case of missiles. The effort to stop their spread is usually dated to November 1982, when President Ronald Reagan signed National Security Decision Directive 70. Titled "Nuclear Capable Missile Technology Transfer Policy," it stated that the United States would "[s]eek cooperation with supplier nations in limiting the export of strategic missile-related hardware and technology." The Missile Technology Control Regime (MTCR), designed toward that end, did not take shape until April 1987.
It took longer still for the MTCR to gather momentum. Not until the early to mid-1990s did its membership cover most potential suppliers of missiles or relevant technologies. Even now, China and five "unilateral adherents," including India and Israel, have not formally joined. Even the 34 full partners in the MTCR are engaged only in a voluntary undertaking, not a legally binding treaty regime.
In the short run, then, nonproliferation demands effort, patience, and the ability to keep outcomes in perspective, points discussed in this space previously. But these virtues have a shortcoming: If we are serenely patient and tolerant of imperfection, how can we distinguish failure from success? Fortunately, enough time has now passed to allow some judgments about the long-term effectiveness of initiatives to restrict the spread of missiles. Some of these lessons may be sufficiently general that we need not wait decades to re-learn them in other areas. For example, another forum for voluntary trade restraints, the Nuclear Suppliers Group, has recently embraced a new list of criteria for sales of enrichment or reprocessing technology. What applies to delivery systems may in many respects also apply to fissile material production.
At least four major policy initiatives have been attempted to stop the spread of missiles. They have varied greatly in their effectiveness.
Export-control diplomacy. Export-control diplomacy, including the creation of the MTCR, can be judged partly effective. In the late 1980s, there were three major exporters of ballistic missiles: the Soviet Union, China, and North Korea. By the early 1990s, Russia and China had been persuaded to accept the MTCR or similar restraints. Argentina, an emerging exporter, was persuaded not to enter the market. But North Korea, which began exporting ballistic missiles in 1987, the year of the MTCR's founding, has accepted no limitations on its exports.
Another shortcoming of export-control diplomacy has been the lack of consistent will to tackle cruise-missile proliferation. Cruise missiles are covered by the MTCR, but as Dennis Gormley has observed, efforts to control their spread have been relatively lax. Moreover, outside of strategic arms control treaties, no effort has been made to restrict nuclear-capable aircraft.
Sanctions and interdiction. Despite their intuitive appeal, sanctions and interdiction have not played a large role against missile proliferation. The sole major supplier of ballistic missiles completely outside of the MTCR, North Korea, has proved effectively immune to these policies. This is partly due to North Korea's ability to adapt to obstacles by using new means of transporting arms shipments, but it's mainly a question of timing. Systematic interdiction efforts only started in May 2003 with the Proliferation Security Initiative, a voluntary "activity" that organizes the seizure of "WMD, their delivery systems, or related materials." A series of UN Security Council Resolutions followed, supplying either general authority for strengthening border controls (UNSCR 1540 of April 2004) or specific authorities for stopping shipments from North Korea (UNSCR 1718 of October 2006 and USCR 1874 of June 2009). But as described in an article in the July 2011 issue of the Nonproliferation Review, North Korea's exports of missiles and missile components had already slowed to a trickle by the early 2000s. Among the relatively numerous seizures of North Korean arms shipments since UNSCR 1874, none have involved missile technology. Interdiction has simply come along too late to make much difference.
Pressure on the buyers. A less prominent but more successful initiative, which probably led to the diminishment of the North Korean missile trade in the first place, is pressure on the buyers of missiles to exit the market. Egypt, Pakistan, the United Arab Emirates, and Yemen -- all states aligned to a greater or lesser extent with the United States and with the West -- appear to have quietly ended their missile-related dealings with North Korea. The Pakistani-North Korean relationship seems to have concluded abruptly in 2001, when Pakistan's A. Q. Khan lost his position as head of Khan Research Laboratories. A handful of news reports have described pressure from Washington on Egypt and Yemen. Libya's connection to Pyongyang seems to have ended as part of its 2003 deal with the United States and the United Kingdom. This sort of pressure has its limits, though. It couldn't separate either Iran or Syria from North Korea. The relationships between these three countries seem only to have deepened, shifting from missile purchases to collaborative development of new missile types.
Ballistic missile defenses. A fourth approach to suppressing missile proliferation has been the development and deployment of ballistic missile defenses (BMD) to dissuade missile importers from making continued acquisitions. "The ultimate goal of missile defense," according to the US Missile Defense Agency, "is to convince countries that ballistic missiles are not militarily useful or a worthy investment and place doubt in the minds of potential aggressors that a ballistic missile attack against the United States or its allies can succeed." Unfortunately, BMD has proved counterproductive in this respect. The report from the Pentagon's 2010 Ballistic Missile Defense Review concludes that the missile threat is only increasing. It finds that regional proliferating states -- a catch-all term for Iran, Syria, and North Korea -- are "increasing the number of deployed systems (and thus raid sizes), shifting from liquid- to solid-fueled systems, and deploying missile defense countermeasures." All of these steps help to overcome BMD, the deployment of which seems to be encouraging larger and more sophisticated missile arsenals.
Several lessons might be drawn from this policy report card. First, as expected, no single "silver bullet"has solved the problem. Different initiatives have contributed to managing the threat, some more than others. Second, efforts to restrict both supply and demand have helped. The two most effective policies have addressed either side of the equation: Export-control diplomacy has reduced supply, while pressure on importers has reduced demand. A third lesson is the relative weakness of coercive action and military tools for nonproliferation purposes. Both interdiction and missile defense have mainly served to stimulate adaptive strategies by the targeted states. Almost comprehensively encircling a deeply isolated opponent is conceivable -- this was the situation with Iraq in the 1990s -- but today's adversaries have more options. Finally, a fourth lesson is the necessity of persistence and political will. If leaders of all political stripes had not plugged away at the problem over the course of decades, even the imperfect results achieved so far would not have been realized.
This last lesson is the most broadly applicable. In the context of enrichment and reprocessing controls, it suggests that no list of criteria alone will prevent states from jumping into the market for fissile-material production technologies -- especially if North Korea or Iran should emerge as illicit nuclear suppliers. As argued previously here, the single most important step that interested governments can take is to provide their nonproliferation bureaus with greater independence and authority. Acting to give nonproliferation sustained attention at high levels may be the best opportunity to ensure that these concerns won't be sacrificed to other agendas.