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The ban treaty: A big nuclear-weapon-free zone?

21 June 2017
Sebastian Brixey-Williams

Sebastian Brixey-Williams

Sebastian Brixey-Williams is project leader at the British American Security Information Council (BASIC), a leading disarmament and arms control think-tank in London. He also...


The nuclear weapons states seem to have accepted the idea that a treaty to prohibit nuclear weapons—known informally as the ban treaty—could indeed be the result of a UN conference being held this June and July in New York City. Nevertheless, some observers maintain that even if a ban treaty were to be negotiated, it would cause harm by distracting from and competing with progress in existing disarmament efforts—such as the Nuclear Non-Proliferation Treaty (NPT), which already mandates all signatories pursue complete disarmament.

Would the ban treaty distract and compete? It might. Multiple, simultaneous efforts at achieving nuclear disarmament could lead to forum shopping, with non-nuclear-armed states seeking to promote disarmament through the stronger ban treaty regime, while nuclear-armed states press on with the NPT. This could mean that more time is spent arguing about what the approach to disarmament is, and less time is spent making much-needed, meaningful progress.

Duplicate efforts at nuclear disarmament could also empower spoilers and create distractions which, given the general lack of political attention to nuclear issues these days, could be problematic. But it’s too early to know either way, and prophecies of this kind have an unhealthy habit of becoming self-fulfilling. The diplomats in the ban treaty negotiations have been adamant that the treaties should not conflict; just to be on the safe side, chair Elaine Whyte Gómez deliberately avoided last month’s NPT Preparatory Committee meeting in Vienna, so as not to create a distraction. And sometimes the reverse is true as well: New initiatives can sometimes breathe new life into old stalemates.

But crucially, these arguments assume that the ban treaty and the NPT are destined to compete. I’d like to offer an alternative perspective: that the ban treaty is more likely to resemble a big nuclear-weapon-free zone (NWFZ). Rarely does anyone say that existing NWFZs are in conflict with cornerstone disarmament or arms control regimes—in fact, most say they strengthen them. So, have we read the ban treaty all wrong?

What’s a Nuclear-Weapon-Free Zone? An NWFZ is a geographic zone where no nuclear weapons are allowed, usually delineated by a treaty. Such treaties consist of a list of strong, and legally-binding prohibitions on nuclear weapons within the states that sign them, traditionally agreed by region. The world has five such treaties, covering South America (Tlatelolco Treaty), the South Pacific (Rarotonga Treaty), Southeast Asia (Bangkok Treaty), Africa (Pelindaba Treaty), and Central Asia. In the wings is a Middle East Nuclear-Weapon-Free Zone, which states have struggled to negotiate for more than 20 years, and recently the idea of a Northeast Asia Nuclear-Weapon-Free Zone has been floated. Additionally, there are four denuclearization treaties covering the seabed, outer space, the moon and other celestial bodies, and Antarctica.

Nuclear-armed states have mixed feelings about NWFZs. On the one hand, they do some of their nonproliferation work for them by strengthening restrictions on nuclear weapons within a geographical region. On the other hand, the act of signing an NWFZ makes opposition to nuclear weapons by non-nuclear-armed states feel more concrete; the mere existence of an NWFZ questions the very legitimacy of nuclear possession. Moreover, while NWFZs have no legal effect on states that have not voluntarily joined them, they can limit possessor states’ freedom of action within that region; for example, New Zealand’s 1987 declaration that it was a place free of nuclear weapons prevented US Navy ships from visiting their ports. For these reasons, NWFZs are typically vehemently opposed by their nuclear neighbors at the time of negotiation, but today nuclear-weapon-free zones and the Nuclear Non-Proliferation Treaty tend to peacefully co-exist.

A bigger, better NWFZ. The ban treaty is likely to look like a unified, extended, and strengthened NWFZ owing to similarities in the legal structure and effect of the treaty, as well as parallels in the language and objectives—although there are, of course, limitations to this reading. But looking at the ban treaty in this way may help nuclear communities integrate the emerging ban treaty into their traditional nonproliferation regimes.

First, the legal status of the ban treaty mirrors that of the NWFZs. It would consist of a subgroup of NPT states making a comprehensive and binding declaration about what kind of nuclear activities are not permitted inside their territories. Like a nuclear-weapon-free zone, the ban cannot directly outlaw nuclear-armed states from going about their nuclear activities without those states voluntarily adopting and incorporating the treaty prohibitions into their domestic law. (In other words, “I can’t tell you what to do, you have to want to do it.”) The ban would bind all states only if the ban treaty’s prohibitions become customary international law—a term which could loosely be described as meaning that the prohibitions are so widely accepted and sustained as the international legal standard of behavior that they bind even non-signatories.

But as I’ve explained elsewhere, it is highly unlikely that the ban would come into effect on non-signatories any time soon. It is not yet clear how many states will sign the eventual ban treaty, though 132 states were in attendance at the March negotiations; consequently, the number of signatories is likely to remain far below the near-universal signature of the NPT with its 190 signatories, even in the medium- to long-term.

Second, the ban treaty could be read as an informal unification of the five existing nuclear-weapon-free zones. While the NWFZs are not homogenous, to some extent the ban treaty brings these regional treaties into a common, planned, unified way of doing things. The fact that states like Brazil, Mexico, and New Zealand—which had previously demonstrated leadership in the establishment of NWFZs—have also been instrumental in driving forward the ban movement agenda shows this is not accidental. Mexican Ambassador Alfonso García Robles, who won a Nobel Peace Prize for his work implementing the Tlatelolco Treaty (the South American NWFZ), hoped that “the territories of powers which possess those terrible tools of mass destruction will become something like contaminated islets subjected to quarantine.” Unifying the NWFZs has also been an explicit aim of the ban treaty movement: Article 36, an organization lobbying for the ban, writes that NWFZs are “important building blocks that should be expanded upon through an international ban treaty.”

As the ban treaty movement reaches into new regions such as Europe—through the participation of Austria, Cyprus, the Holy See, Ireland, Liechtenstein, Macedonia, Netherlands (a NATO state), San Marino, Sweden, and Switzerland— the ban treaty could also be a de facto extension of the NWFZ model. In fact, it’s possible to look at the ban treaty as a radical rethinking of the concept of nuclear-weapon-free zones, not delineated by region or even geography. For instance, if member states are banned from financing nuclear weapons, then portions of the financial sector may resemble a new kind of nuclear-weapon-free space.

Third, the language of the ban treaty’s opening articles mirrors those found in NWFZs. For example, while the Nuclear Non-Proliferation Treaty’s Article 1 is primarily concerned with the transfer of nuclear secrets and technologies from one state to another, the NWFZs typically begin by listing prohibitions that apply to the territories of signatories. The ban treaty clearly takes this latter approach, and diplomats at the negotiations are debating how to strengthen the prohibitions to fill gaps and loopholes. Which means that as well as unifying these zones, the ban treaty could effectively supersede them as the new standard for nuclear-free activities.

Limitations. There are, of course, ways that the proposed ban treaty might differ from the classic NWFZ model, relating to how it was negotiated, its reception among the nuclear-armed states, and perhaps above all, the goals of its negotiators.

First, while the ban treaty process is heavily UN-oriented, there tended to be minimal United Nations involvement in negotiations for nuclear-weapon-free zones; instead, most were regionally negotiated. By contrast, the ban treaty negotiations have been conducted in a conference established by the UN General Assembly. In a nutshell, while the NWFZ movements emerged in the international system in a more decentralized way, the ban is being negotiated in the center and radiating outward.

Second, acceptance of the ban treaty may be less forthcoming than for the nuclear-weapon-free zones. In some cases, nuclear weapon states have willingly endorsed some regional NWFZs by signing protocols that give assurances that the treaty will be respected, although they’ve withheld support for others. But the ban treaty movement’s morally charged language, its stated aim of including outsiders to the insiders’ process of nuclear disarmament—what Jennifer Knox at Global Zero has called “subversive arms control”––and the general feeling among the nuclear weapon states that the organized weight of the entire UN General Assembly is against them may limit their willingness to make conciliatory concessions. It remains to be seen whether the ban treaty will be incorporated into the NPT to the same extent as the NWFZs.

Third, framing the nuclear ban treaty as an extension of the nuclear-weapon-free zone movement may be controversial among advocates and negotiating parties, who hope to make use of global momentum, optimism, and a sense of inevitable success to build support among states. This is reflected in campaign messages such as “We’re banning nuclear weapons,” which seeks to frame the ban treaty movement as a radically new and unhindered approach. In contrast, the NWFZ framing is more conservative, to the extent that it places no moral responsibilities on states to partake in the negotiations, and consequently appeals to positions that are more morally relativist. Reducing the effort to ban nuclear weapons entirely to just another nuclear-weapon-free zone could suck some wind out of the movement rhetorically, even if it has no effect on its legal status.

Ways forward. The interactions between the ban treaty and the NPT will need to play out in their own time. But to me, the potential harms appear to be overstated. Opposition to the ban treaty can also be viewed as an expression of nuclear-armed states’ apprehension of the new, their unwillingness to accept illegitimacy in the eyes of the majority, and as a means—consciously or unconsciously—to find a scapegoat for the stalled disarmament and arms control agendas seen in recent years. Instead, nuclear-armed states should look at the ban treaty’s actual legal implications and approach it with more of an open mind, finding opportunities to conceptually integrate the treaty into the existing patchwork of nonproliferation regimes and further their disarmament objectives. Seeing the ban treaty as a nuclear-weapon-free zone may be a way for nuclear-armed states and their allies to open new doors to engagement with the non-nuclear weapon states, while at the same time allowing them to save face. Indeed, as nuclear arms control and verification specialist Andreas Persbo points out, NWFZs are explicitly recognized in Article VII of the Nuclear Non-Proliferation Treaty, which says that NWFZs do not affect “the right of any group of States to conclude regional treaties” to “assure the total absence of nuclear weapons in their respective territories.” The ban treaty might be integrated via the same provision.

The framing could benefit ban treaty advocates too. Although advocates will want to find ways to preserve their morally-charged messaging, and ensure that the prohibitions in the eventual treaty are applied worldwide, the framing offers a strong comeback to the charge that the ban treaty is in competition with the NPT. In fact, this framing could offer ban proponents a new tool to convince states that are currently sitting on the fence to sign the treaty.