The threat of landmines is garnering much-needed attention again. In April, an official at the U.S. Department of Defense indicated that, contrary to expectations, the new Biden administration would maintain the Trump administration’s policy on antipersonnel mines. This surprised and dismayed many observers, since Trump had reversed an Obama-era decision that brought the United States into closer alignment with the global ban on these perniciously deadly weapons. The revised Trump policy instead envisioned a renewed use of antipersonnel mines in U.S. military operations.

During the 2020 presidential campaign, then-candidate Joe Biden had promised to promptly roll back this policy. The April 2021 announcement thus led to a swift backlash, and U.N. Ambassador Linda Thomas-Greenfield shortly after declared that the Biden administration would undertake a formal review of U.S. landmine policy. At the time of this writing, the review is ongoing.

In many areas of foreign policy, the Trump administration departed radically from prior practice. As international relations scholars who have studied U.S. landmine policy, we assess the impact of the norm against antipersonnel mines on American military operations. We find that the very reasonable concerns that the Trump policy could mark a return of these armaments to American warfighting have not been borne out. A careful examination of what changed — and what did not — reveals that the policy shift had little practical effect and demonstrates considerable continuity despite the typical bluster. Indeed, regardless of changing geopolitical conditions, U.S. military postures and commitments, and domestic political leadership, the United States continues to engage with — and be constrained by — the normative prohibition on antipersonnel mines.

The Global Stigma

Antipersonnel mines are small explosive devices placed on or under the ground “designed to be exploded by the presence, proximity or contact of a person” (Mine Ban Treaty, Art. 2.1). Owing to their low cost, availability, and ease of use, the weapons featured extensively in armed conflicts around the world in the second half of the 20th Century. Once deployed, most antipersonnel mines remain active indefinitely and cannot distinguish between combatants who may be legitimately targeted in war and civilians who must be protected. By the early 1990s, millions of deployed mines from newer civil wars and historical conflicts generated thousands of deaths and tens of thousands of casualties annually, overwhelmingly among civilians.

Growing recognition of the severe humanitarian consequences spurred a global civil society movement aimed at their elimination. That culminated in the 1997 Antipersonnel Mine Ban Treaty, also known as the Ottawa Convention (the treaty does not prohibit larger anti-vehicle mines, which are regulated under international law). Today, antipersonnel mines are almost universally stigmatized: 164 countries have joined the Mine Ban Treaty, committing to never develop or use the weapons and to remediate their enduring effects by clearing contaminated land and aiding mine survivors and affected communities. Myanmar is the only country still actively using antipersonnel mines, though non-state armed groups continue to use mines and improvised explosive devices in a number of territories. Even powerful non-parties — notably including the United States — have abandoned antipersonnel mines as a weapon of war despite refusing to formally join the treaty.

Some analysts claim that, since the United States never formally ratified the Mine Ban Treaty, the treaty’s blanket prohibition on antipersonnel landmines does not constrain the U.S. in any way. Yet the prohibition against using antipersonnel mines is not only an international treaty but also a norm that the United States has tacitly accepted. Norms — standards of appropriate behavior for certain kinds of actors (like states)– can shape behavior, even when they are not backed by legal obligation. The United States may not be legally required to fully comply with the prohibition against antipersonnel mines, but has nonetheless increasingly followed it since the treaty entered into force.

US Landmine Policy

As the preeminent global military power, the United States has maintained an ambivalent relationship with the antipersonnel mine ban since its inception, both endorsing its humanitarian spirit while continuing to insist upon the necessity — and technological superiority — of U.S. mines. The United States has long contended that its use of “non-persistent” landmines containing self-destruct or self-deactivating capabilities and military professionalism did not contribute to the global humanitarian antipersonnel mine crisis. Yet successive Democratic and Republican administrations continued to interact with the mine ban movement and norm, and these processes exerted influences that have informed U.S. landmine policy up to the present day.

President Bill Clinton used a 1994 speech at the United Nations General Assembly to call for “the eventual elimination” of antipersonnel mines. But the United States simultaneously sought to direct diplomatic efforts to preserve its own weapons and refused to join the resulting Mine Ban Treaty. In keeping with its broader skepticism of binding multilateral constraints on security policy, the George W. Bush administration released a revised landmines policy in 2004 that rejected the prohibitionary approach contained in the Mine Ban Treaty. Yet the Bush policy also phased-out persistent “dumb” landmines in favor of so-called “smart” “non-persistent” antipersonnel and anti-vehicle mines, in recognition of the unacceptable harm caused by traditional landmines.

In 2014, the Obama administration announced that the United States would no longer develop antipersonnel mines that violated the Mine Ban Treaty, would not use antipersonnel landmines outside the Korean Peninsula, and would destroy landmine stockpiles not required for the defense of the Republic of Korea. At the same time, the administration committed to “pursue material and operational solutions that would… ultimately allow us to accede to the Ottawa Convention.” While rightly hailed as an important shift towards greater — though still incomplete — adherence to the mine ban, the Obama policy also represented a codification of longstanding U.S. practices reflecting the declining prevalence of antipersonnel mines.

One of the defining features of the Trump administration was the president’s desire to undo his predecessor’s legacy in virtually every policy area. It was therefore not altogether surprising that, in January 2020, the Department of Defense announced that Trump had decided to substantially weaken the 2014 restraints. The revised policy allows U.S. forces to use non-persistent antipersonnel mines anywhere in the world and lowers the threshold for authorization from the president (which had been in place since 1996) to regional combatant commanders. In justifying the new policy, a DoD spokesperson argued that antipersonnel mines “remain a vital tool in conventional warfare that the United States military cannot responsibly forgo” in an “era strategic competition.”

What Actually Changed

The Trump policy represented a significant departure from the prior status quo, raising serious questions regarding the extent to which the United States is still constrained by a norm against antipersonnel mines. The move was strongly condemned by civil society activists and other States, including allies. (Full disclosure: Co-author Bower previously argued that the Obama-era policy would not attract the Trump administration’s attention due to the extent to which antipersonnel mines had been marginalized in U.S. military training, procurement, and operational planning. In this light, the January 2020 announcement looks like a substantial reversal of this trend, albeit one that was consistent with the administration’s hostility to international restraints and policy achievements associated with President Barack Obama. The impetus for the review that prompted the Trump administration shift likely came from among a few committed holdouts in the U.S. military’s senior ranks who still insist such mines are necessary.)

Yet since the January 2020 announcement, there is little evidence that antipersonnel mines have re-entered U.S. military practices. In other words, despite pronouncements to the contrary, the practical changes appear to be minimal – continuity rather than disjuncture are the order of the day.

First and most notably, there is no suggestion that U.S. armed forces have used antipersonnel mines since the start of 2020. This is in keeping with three decades of U.S. practice: American forces have not used antipersonnel mines since the 1991 Gulf War, with one minor exception in Afghanistan in 2002. There are no active minefields under U.S. control anywhere in the world, including on the Korean Peninsula, where the landmines already in and near the Demilitarized Zone are the responsibility of South Korean forces, not the United States.

While the Trump policy substantially relaxed the conditions governing antipersonnel mine use, they are still envisioned for “major contingencies or other exceptional circumstances” when comparable alternative systems are not available; antipersonnel mines “will not be a default option.” This framing provides further evidence of the subtle but important ways that the mine ban norm has raised the threshold for assessing antipersonnel mines from “normal” to “exceptional” tools of war.

Moreover, the United States has not procured new antipersonnel mines since the policy announcement, continuing a more than two-decade production pause. The relevant fiscal year 2021 budget contained no funding for new antipersonnel mines. However, in an August 2020 response to a request for information from a group of U.S. senators and representatives earlier in May, DoD indicated that it intends to develop new “terrain shaping area denial munitions” that would include antipersonnel mines governed by current U.S. policy. Publicly available information does not disclose how far along this program has advanced. Prior to the 2020 announcement, all systems under development were designed to be compliant with the Mine Ban Treaty by requiring a U.S. solider to initiate denotation, rather than containing a “victim-activated” mode.

Without new systems coming online, U.S. antipersonnel capabilities will continue to atrophy. Existing U.S. stockpiles of “non-persistent” mines are designed to become obsolete rather than be maintained: once their batteries wear out, they cannot be replaced. In announcing the revised Trump policy, the Pentagon confirmed that the United States no longer holds any “persistent” antipersonnel mines in its operational stockpiles. The U.S. has invested over $2 billion researching alternative technologies that could replace antipersonnel mines since the late 1990s, further evidence of how it has adapted to changing international conditions.

The Trump administration also maintained the longstanding diplomatic and humanitarian engagement with respect to landmines. The United States has not sold or otherwise transferred antipersonnel mines to any state or entity since 1992. In 2019 and 2020, the United States continued to be the top funder for mine clearance worldwide and published its annual report on those efforts, To Walk the Earth in Safety. Moreover, the United States attended the Mine Ban Treaty review conference in November 2020 as an observer, indicating support (or at least the appearance of support) for the norm.

Such efforts to maintain U.S. standing as a good international citizen belie the suggestion that the Trump administration was entirely unconcerned with the mine ban norm. Notably, the more permissive U.S. policy does not appear to have normalized antipersonnel mines among other states. Unlike in other policy domains, therefore, the Trump era has not produced a wider backsliding in the international community.

Public Pressure 

Whether norms constrain or not is rarely a simple yes or no question. Instead, norms inform policy choices to different degrees depending on context and the extent of their entrenchment. The norm against antipersonnel mines is now firmly established internationally and has undoubtedly contributed to their declining relevance in U.S. military thinking, despite the more recent change of tone. As a result, the reintroduction of these weapons would require significant changes to training, deployment, and combat operations.

The implications of this more permissive policy are also muted by the anticipated and actual response from others. The Trump administration’s review of U.S. landmine policy was conducted without public acknowledgement until after its completion. Until the new policy was announced, few people outside DoD knew that the administration was considering loosening restrictions on the use of landmines. The secrecy of the review process suggests that the Trump administration knew the result would be met with an outcry, and sought to evade public scrutiny. Moreover, although the review was completed in 2018, it was not publicly announced until 2020 — under a new Secretary of Defense — suggesting a hesitation to defy the international consensus against antipersonnel mines that has been gathering pace in the United States as well.

Even before taking office, President-elect Biden faced public calls to swiftly reverse the Trump policy. The widespread condemnation of the Biden administration’s initial stance and the hasty announcement that a formal policy review would be undertaken is reminiscent of the Obama administration’s initial landmine policy review in 2009, which retained the Bush-era position. After public outcry at that time, the administration committed to a fuller review that ultimately produced the 2014 policy. Public pressure from experts and allies in support of the ban on antipersonnel mines underscores the continued salience of the norm. In June, a bipartisan congressional letter led by Democratic Senators Patrick Leahy of Vermont and Jack Reed of Rhode Island urged Biden to “reinstate the Obama policy, and by doing so reaffirm the United States as a leader in the global effort to reduce the carnage caused by antipersonnel mines.”


Despite the shocking announcement that the United States would consider using landmines anywhere in the world, most fears have not been born out. Indeed, the U.S. abandonment of antipersonnel mines was not initiated by the Obama administration but has developed in fits and starts since the mid-1990s. As a consequence, the norm against antipersonnel mines has become increasingly entrenched among U.S. policymakers and members of the armed forces. Instead of leading to new development and use of landmines, recent experience shows how normative restrictions can be stronger than the letter of the law in shaping practice.

What can be expected from the current Biden policy review? The most likely outcome would be a return to the Obama-era status quo, which could be implemented by presidential directive. Reverting to the 2014 policy would require the cessation of research and development for new types of antipersonnel mines, notably the current “terrain shaping area denial munitions” discussed above. However, Biden could go further than Obama by eliminating the 2014 policy’s exemption that permitted continued stockpiling and potential use of antipersonnel mines on the Korean Peninsula, thereby removing the final stated impediment to a comprehensive elimination of the weapons. The Biden administration could also potentially seek ratification of the Mine Ban Treaty in the U.S. Senate. In 2010, 68 Senators endorsed the idea of the United States joining the treaty, but this bipartisanship appears impossible in the present political context. Yet short of officially joining the treaty, the new administration can signal its support for the norm by enhancing U.S. participation at Mine Ban Treaty meetings and increasing its funding for humanitarian mine action.

Ultimately, the Trump policy is more notable for what it did not lead to rather than what did. Despite the change in official policy, the United States did not move towards violating the norm against antipersonnel mines in practice. There is now an opportunity to set the U.S. much more clearly on the side of humanity in decisively eliminating antipersonnel mines.

IMAGE: South Korean soldiers remove landmines inside of the Demilitarized Zone (DMZ) on October 2, 2018 in Cheorwon, South Korea. South and North Korea began removing a small portion of land mines scattered across the heavily fortified border area as part of an agreement at the previous month’s Inter Korean summit. (Photo by Song Kyung-Seok-Pool/Getty Images)