The U.S. Landmine Policy Complies with International Law
In late January, the United States replaced the Obama Administration’s 2016 landmine policy, which was first introduced in 2014. That policy had proscribed the use of antipersonnel landmines beyond the Korean peninsula.
In taking this step, Defense Secretary Mark Esper explained, “[i]n light of the current and emerging strategic environment, and the critical warfighting capabilities that area denial systems can provide, the President has decided to cancel Presidential Policy Directive-37 (PPD-37), which set forth a revised U.S. policy regarding landmines in January 2016.” The new policy authorizes combatant commanders to employ non-persistent landmines, including antipersonnel landmines, “when necessary for mission success in major contingencies or other exceptional circumstances.” It imposes no geographical limitations. However, the policy reaffirms the U.S. commitment to not use persistent landmines, namely those that do not incorporate self-destruct and self-deactivation features.
Critics of the new policy, such as the European Union, the International Committee of the Red Cross, and various non-governmental organizations, as well as some domestic lawmakers, have called on the Trump Administration to reverse its position. Ottawa Convention President Ambassador Osman Abufatima Adam Mohammad has condemned the U.S. decision as “going against its long-standing commitment to work towards the eradication of the suffering caused by anti-personnel mines.” Those advocating for yet another U.S. reversal are motivated by concerns about civilian casualties from mines and the debilitating impact of unexploded, persistent antipersonnel landmines on communities.
In our view, improper employment or misuse of antipersonnel landmines is responsible for such consequences, not the inherent nature of the weapon. But whatever the case, the opposition to the Trump Administration’s policy reversal, and the many calls for an outright ban, beg the question of whether international law permits the use of antipersonnel landmines by the United States in the first place. As discussed below, we believe that it does.
The United States became a party to Amended Protocol II annexed to the Convention on Certain Conventional Weapons (Amended Mines Protocol) in 1999. Currently, 106 nations, including all five permanent members of the U.N. Security Council, are States party to the treaty. The Amended Mines Protocol regulates the use of landmines but does not prohibit such use. Key elements of the Protocol include a ban on the use of ground-delivered antipersonnel landmines without self-destruct and self-deactivation mechanisms, unless they are clearly marked, fenced, and monitored; a requirement that mines delivered remotely by aircraft or artillery have self-destruct and self-deactivation features; and a condition that antipersonnel landmines be detectable so they can be located and safely removed.
The detectable and non-persistent GATOR mine system, which is used for both diversion and immobilization of enemy forces and area denial, is an example of a U.S. landmine that complies with the provisions of the instrument. It can be set to self-destruct at four hours, fifteen hours, or fifteen days after activation, and its battery expires after forty days, thereby limiting risk to civilians.
The current landmine policy specifically references the obligation to comply with the Amended Mines Protocol. Indeed, U.S. policy is more restrictive than required by the Protocol, for it completely prohibits the use of any persistent landmines, that is, landmines without self-destruct and self-deactivation mechanisms. Further, while the instrument provides that all remotely delivered antipersonnel landmines used outside of marked areas must self-destruct and self-deactivate within thirty days of emplacement, U.S. policy requires that all landmines—not just remotely delivered antipersonnel landmines—be designed to self-destruct within thirty days of activation.
In addition to the Amended Mines Protocol, proponents of a ban on antipersonnel landmines have urged the United States and other non-party States to become party to the 1997 Anti-Personnel Landmines Convention—commonly referred to as the Ottawa Convention, which entered into force in 1999. Although it is often called a “mine ban” treaty, the Ottawa Convention only encompasses antipersonnel landmines, not other types of landmines, such as anti-vehicle landmines. The treaty prohibits the use, development, production, acquisition, stockpiling, retention, or transfer of antipersonnel landmines under any circumstances. Currently, 164 nations are party to the Ottawa Convention. The United States, Russia, China, and over 30 other nations are not. Accordingly, its obligations do not bind the United States unless they reflect customary international law.
Treaty Obligations as Customary International Law
Article 38 of the Statute of the International Court of Justice, a provision with which all States agree, characterizes “a general practice accepted as law” as a primary source of law, together with treaties and general principles of law. Such norms are known as “customary international law.” States make binding customary international law through “extensive and virtually uniform” State practice engaged in, or refrained from, out of a sense of legal obligation (opinio juris). Consistent State practice that merely reflects State policy or practical interests does not suffice. The question is whether the Ottawa Convention’s prohibition on the use of antipersonnel landmines has come to reflect customary international law for non-party States like the United States.
A majority of States are party to the Ottawa Convention, although, as noted, there are significant States that are not. Moreover, and very tellingly, some State parties have reserved the right to conduct combined operations with non-party States that continue to use antipersonnel landmines. These reservations signal that the State parties in question do not consider the prohibition to be binding on non-party States as a matter of customary law. After all, if the prohibition was customary, cooperation with States employing antipersonnel landmines could expose State parties to responsibility for their role in the unlawful use of a prohibited weapon. In fact, the International Committee of the Red Cross’ extensive study on customary rules observes “it cannot be said” the proscription on the use of anti-personnel mines reflects customary international law.
But even if such a prohibition on the use of antipersonnel landmines existed in international law, States that repeatedly object to a customary international law rule during its development arguably are not bound by that rule. The International Court of Justice, in its Fisheries case, acknowledged this possibility of “persistent objection,” a view shared by the United States. In this regard, the United States has consistently maintained its right to use non-persistent antipersonnel landmines. Even though advocates of a complete antipersonnel landmines ban point to the United States’ long-standing political commitment to the “eventual elimination” of antipersonnel landmines, as a matter of law the United States has always reserved its right to employ them. Thus, even assuming a blanket prohibition on antipersonnel landmines has emerged as customary international law, the United States would not be bound.
Conduct of Hostilities Rules and Antipersonnel Landmines
While the United States is not bound by the Ottawa Convention’s obligations or any customary international law analogue, non-persistent antipersonnel landmines are still subject to customary conduct of hostilities rules found in the law of armed conflict. Prominent among these is the superfluous injury rule; its modern formulation found in Article 35(2) of AP I. This rule proscribes the employment of any weapon “of a nature to cause superfluous injury or unnecessary suffering.”
While the United States has not ratified this treaty, it considers the rule to be customary international law. It also appears in treaties to which the United States is party, such as the 1899 and 1907 Hague Regulations and the Convention on Certain Conventional Weapons, and is cited in U.S. manuals, such as the Department of Defense Law of War Manual and the Department of Army Field Manual on the Law of Land Warfare. The United States considers the phrase “calculated to cause superfluous injury” to be a more accurate articulation of customary international law and focuses “on the design and intended purpose rather than every remote possibility of weapon injury.” Simply put, the rule prohibits weapons designed to unnecessarily increase the suffering of those attacked beyond what is justified by military necessity.
A second prohibition that bears directly on the use of antipersonnel landmines bans the use of inherently indiscriminate weapons against combatants, members of organized armed groups, and civilians who are directly participating in the hostilities. As noted in the Law of War Manual, the United States considers this prohibition to be a rule of customary law of armed conflict. According to the rule, weapons that cannot be directed at a military objective or have effects that cannot be limited as required by the law of armed conflict—for instance because they necessarily cause disproportionate collateral damage—are prohibited.
There is no international consensus that non-persistent antipersonnel landmines violate these customary rules. The ICRC has conceded as much. Moreover, the negotiating history of the Ottawa Convention supports the conclusion that the weapons do not, as such, run afoul of these prohibitions. Indeed, a proposal to include language in the preamble “recognizing that anti-personnel mines are of such a nature” to cause superfluous injury and are inherently indiscriminate was not included in the final agreement.
Instead, violation of these rules is to be determined on a case-by-case basis. For instance, consider the superfluous injury rule. A mine filled with shards of glass undetectable by x-ray would be calculated to cause superfluous injury for there is no military rationale for using glass to harm the enemy. And as to the prohibition on indiscriminate weapons, non-persistent antipersonnel landmines can be directed at military objectives in certain operational contexts, and the effects of antipersonnel landmines are capable of being controlled by, for instance, self-deactivation and self-destruction mechanisms. Thus, they are not per se inherently indiscriminate. In fact, all landmines in the U.S. operational inventory include such safety features to limit unintended harm to civilians.
While the Trump Administration’s antipersonnel landmines policy has attracted significant international criticism, especially from the growing movement to ban landmines, careful analysis leads to the conclusion that it is compliant with the legal obligations that bind the United States. Despite the discontinuation of antipersonnel landmines use by a large majority of States, an outright prohibition on antipersonnel landmines has not crystallized as customary international law, nor is the use of antipersonnel landmines unlawful per se under customary conduct of hostilities rules because they are not calculated to cause superfluous injury nor inherently indiscriminate. Furthermore, the parameters for antipersonnel landmines use announced in the policy comply with or exceed the protections found in the Amended Mines Protocol.
Ultimately, the policy reflects a strategic decision regarding how to address an international environment in which great power competition is growing. Potential rivals—principally Russia, China, Iran and North Korea—have been unwilling to accept broad restrictions on the use of landmines. The U.S. policy is reflective of a desire not to cede advantage to these States. Nevertheless, the protection of civilians during armed conflicts, and a firm commitment to the law of armed conflict, remain foundational principles of U.S. military operations, ones that will inform any use by the United States of antipersonnel landmines.
Major Heather Tregle is a Military Professor of International Law at the Stockton Center for International Law at the U.S. Naval War College.
Lieutenant Colonel Durward Johnson serves as Military Professor of International Law and Associate Director for the Law of Land Warfare at the Stockton Center for International Law at the U.S. Naval War College.
Lieutenant Colonel John Cherry is Deputy Chair and Military Professor of International Law at the Stockton Center for International Law at the U.S. Naval War College.
The views expressed here are their own and do not represent those of the U.S. Naval War College, the Department of the Navy, the Department of Defense, or any part of the U.S. government.