By Joseph R. Epstein
The 2017 threat assessment from the Director of National Intelligence labeled Russia, China, Iran, and The Democratic People’s Republic of [North] Korea (DPRK) as major threats to national security, citing their ambition to develop and modernize weapons of mass destruction (WMD) and the associated delivery systems. Recent developments have elevated a nuclear-capable DPRK to the most pressing national security concern.
Without debating the merits and alternatives, intercepting the DPRK’s test launches is one of the remaining options to disrupt the further development of their missile program. Despite nearly exhaustive efforts by the United States and the international community, measures to curtail the DPRK’s missile program through United Nations resolutions, sanctions, and diplomacy, their capabilities have grown at a rate previously not believed possible. United States intelligence now anticipates they will have a nuclear-equipped intercontinental ballistic missile (ICBM) capable of reaching the mainland United States by 2018.
The greatest technological hurdle remaining before an operational ICBM can threaten the United States is the reentry vehicle that protects the nuclear payload from the earth’s atmosphere. By intercepting the test launches, the United States could prevent the DPRK from gathering data from the launches critical to the program. The question becomes, from a purely legal basis, does the United States have the legal authority to intercept a foreign nation’s unarmed missiles over international airspace?
A nation’s right to self-defense has been a fundamental principle of international law, codified in Article 51 of the United Nations Charter. The more expansive doctrine of anticipatory self-defense and its subsequent variations dating back to the Caroline incident of 1837 remains the basic premise for the anticipatory use of force.
How does a nearly 200-year-old raid on a barge justify intercepting an ICBM? The laws governing when a nation has the legal right to launch a strike is the subject of debate. Article 51 of the UN Charter has been interpreted not to restrict a nation to retaliation. The doctrine of anticipatory self-defense allows for use of force, proportional to the threat when faced with an imminent attack, a nation has no peaceful alternatives. “Imminent threat” becomes the operative phrase and has resulted in various finite distinctions, but whether termed preemptive, preventative, or any of the variations, they all involve the use of force before an adversary can act.
Anticipatory self-defense has become an essential—if controversial—tenet of international law that has been reinterpreted to fit various situations. Any action against the DPRK would likely be categorized preventative. Loosely defined, the use of force in anticipatory self-defense is motivated by a desire to eliminate or minimize a threat before it fully develops, as opposed to the more immediate threat of preemptive. Consensus while rare, and nearly unheard of when it comes to supporting the violation of a nation’s sovereignty, has not been an absolute bar to legitimate anticipatory force. Operation Opera, an Israeli strike on an Iraqi nuclear reactor, and Operation Orchard, another Israeli strike on a nuclear reactor, highlight reasoning used to justify anticipatory self-defense.
Applying the three-part test from Caroline—imminent threat, failure of alternatives, and proportionality—there is reason to believe intercepting the DPRK’s missiles can broadly be interpreted to fall within the accepted limits of international law. Common throughout the limited samples of preventative uses of force is the persistent threat that a hostile nation or actor was developing a credible WMD threat. The threat in these cases cannot be strictly construed as the imminent threat of use, but the development of a capability to produce WMDs once acquired not reasonably withdrawn. In both Israeli operations, had they allowed an explicitly hostile nation, on the verge of developing its nuclear capability to continue unimpeded, they would surely face the threat in the future.
Both the Syrian and Iraqi governments had threatened the state of Israel. Similarly, the DPRK has consistently threatened the United States through public statements, repeated nuclear tests, and the aggressive development of its missile program. The Israeli government relied on force as a last option. The Syrian and Iranian governments, against the directives of the international community, continued to pursue weapons-quality nuclear programs in secret. Both nations were under significant political and economic pressure applied through internationally supported sanctions. To the same ends, the UN has passed eight resolutions since 2006 and the United States has imposed its own unilateral sanctions to no avail. The DPRK has stated publicly—and has made clear through its actions—it has no intention to halt development of its ICBM or nuclear weapons program.
While Israel was not expecting a nuclear attack, it rationalized the preventative use of force by arguing that to wait any longer would take them past a point of no return. The United States is approaching a similar juncture. The DPRK has clearly demonstrated its nuclear capability and is on the verge of developing a missile that can reach the U.S. mainland. The natural defense of distance is slowly eroding as the DPRK increases the range of its missiles, and it is only a matter of time before they can deliver a WMD.
An all-out preemptive strike against the entire military infrastructure would likely not be proportional. However, force limited to missile intercepts would provide the United States the security it needs, minimizing the threat in a proportional and legally justifiable fashion. As tensions ratchet up, the topic is one that deserves further discussion as the world’s most dangerous conflict trends towards escalation.