Throughout the nuclear age, the United States, Russian Federation, China, France, and the United Kingdom – the five states permitted by the 1968 Nuclear Nonproliferation Treaty (NPT) to possess nuclear arsenals (the “NPT nuclear five”)1– have criticized other nuclear states, or each other, for engaging in dangerous or destabilizing behavior with regard to their nuclear forces.2 Criticisms have implicitly or explicitly called out offending states for deviating from behavior associated with “responsible” nuclear states.3

But what exactly constitutes responsible behavior for nuclear-armed states, and what norms or rules should they follow?

The State of Play

Nearly 50 years after the NPT distinguished between nuclear haves and have-nots, the NPT nuclear five have little agreement, whether formal or informal, regarding norms of behavior for nuclear-armed powers. Many aspects of fielding a nuclear force, from posture, conduct, communication of intent, to how their leaders – as heads of state and military commanders wielding existentially powerful weapons – should interact with each other, are not guided by any protocol. This leaves the definition of either responsible or reckless nuclear behavior hazily defined and overly reliant on an assumption that a shared, but unwritten, understanding of the difference between the two exists. With global anxiety about nuclear risks on the rise, it is long overdue for the NPT nuclear five to discuss seriously what they think represents sober, responsible behavior and stewardship of nuclear weapons, and how this aligns with their unique responsibilities to uphold international peace and security as permanent members of the UN Security Council. These five states should seek to address fundamental questions, such as:

  • How does their conduct as nuclear powers avoid or reduce the risk of nuclear incidents or accidents?
  • How does their conduct, and means of communication on nuclear matters, reduce the risk of miscommunication, brinkmanship, and war?

Across the nuclear age, there has been a great deal of discussion, but very little consensus, regarding how to avoid miscommunications and misunderstandings that can raise nuclear tensions or precipitate nuclear crises. Outside of a few “hotlines,” and a small number of Cold War-era agreements between the United States and Russia, there is little evidence of shared understandings or protocols regarding what nuclear powers can and should do to prevent crises from metastasizing into nuclear conflicts.

A Possible Starting Point

How should this shortfall be addressed? A useful first step would be for the NPT nuclear five – who generally meet once or twice a year in their specific capacity as nuclear states (often in pursuit of an elusive “solidarity” to counter criticisms, lately much louder, that they are not doing enough to pursue nuclear disarmament) – to begin serious and sustained negotiations beyond these meetings on drafting a politically-binding “Nuclear Code of Conduct.” International codes of conduct seek to articulate core principles about what constitutes acceptable and unacceptable behavior within a specific domain, for members of a specific group of states, or some combination of both. For the NPT nuclear five, “acceptable” could be defined as what constitutes safe, secure, stabilizing behavior regarding their nuclear forces (and by extension, also helps identify what is destabilizing, reckless behavior).

Discussion on core principles would also provide an opportunity for the NPT nuclear five to debate how they view these forces as contributing to national and international security. They could also assess how they communicate this contribution (in words and actions, such as military exercises) with each other and the broader international community. Critically, the code could be based on (and the text could lead with) the maxim that served as the foundational principle of the first U.S.-Russian bilateral agreements to reduce offensive nuclear delivery systems: “A nuclear war cannot be won and must never be fought.”4 With U.S.-Russian nuclear arms control talks on indefinite hiatus (and given the poor state of the INF Treaty), now is a particularly important time for the NPT nuclear five to collectively embrace this principle and seek to integrate it into a joint agreement that seeks to reduce nuclear risk.

The NPT nuclear five should take positive steps to demonstrate to the international community – and each other – that they take seriously the new, more complex, and more dangerous present nuclear environment.

The NPT nuclear five do not lack for ideas or certain implicit (albeit vague) understandings regarding responsible nuclear behavior, but as a group they have appeared in sync only sporadically, and usually only when countering criticisms by non-nuclear states. The NPT nuclear five’s opposition to the new Treaty on the Prohibition of Nuclear Weapons (TPNW) includes valid objections to the text’s lack of clarity on key definitions, failure to articulate a coherent process for implementation or enforcement, absence of a verification regime, and backpedaling on the importance of the NPT’s Additional Protocol in addressing nuclear proliferation concerns. But the NPT nuclear five should also acknowledge that the treaty, however flawed, represents a plaintive cry by non-nuclear states who feel shut out of any process to meaningfully address rising nuclear risks. Are their fears unjustified at a time when Admiral Mullen, the former Chairman of the Joint Chiefs of Staff, stated in a late November 2017 television interview that “I think [nuclear conflict is] more probable than it used to be, and it scares me to death”?5 Simply dismissing the TPNW is not enough; the NPT nuclear five should take positive steps to demonstrate to the international community – and each other – that they take seriously the new, more complex, and more dangerous present nuclear environment, and that they recognize the importance of working together to clearly and publicly articulate how their nuclear forces can contribute to international security.

The NPT nuclear five should convene to negotiate a nuclear code of conduct along two parallel but mutually reinforcing tracks.

One track should pursue a common lexicon on nuclear forces, nuclear deterrence (the central organizing principle and justification for their forces), nuclear risk, and nuclear stability (i.e. how to define a stable strategic relationship between themselves as nuclear powers). The second track should focus on identifying the core principles of how nuclear forces contribute to their roles and responsibilities as guardians of global peace and security and stewards of international order.

A Common Lexicon

The first track would resuscitate a good idea – the attempt to identify and define key terms associated with nuclear weapons – that had a star-crossed half-life before having a quiet roll out as the P5 Glossary of Key Nuclear Terms at the 2015 NPT Review Conference. The glossary was a frustrating experience for the officials and experts involved, but the process is worth revisiting as either a soft or hard reboot.6 The history of U.S.-Russian nuclear arms control negotiations demonstrates that it can take years of tough negotiations through on-again, off-again talks to develop the shared definitions and concepts necessary to reach substantive agreements. There is no long-term future for multilateral negotiations addressing nuclear risk and nuclear force reductions absent the development of a common language and lexicon; discussions on a nuclear code of conduct could serve as a forum for returning to this difficult but important task.

The Code of Conduct

The second track would focus on the code itself, beginning with discussions of what each NPT nuclear five member considers the core principles of responsible behavior as a nuclear-armed state. These could include the following:

  • how they define “responsible” nuclear behavior and how they implement this concept in their nuclear strategy and posture;
  • how they understand the relationship between their nuclear forces and their responsibility to uphold international peace and stability;
  • discussions of what constitutes nuclear risk, how and why it is increasing or decreasing due to certain behavior, and what the NPT nuclear five can do to reduce risks (even “strawman” critiques of non-NPT nuclear states would be useful, so long as these critiques circled back to specifics about how a “responsible” state should act); and
  • how nuclear force policies, strategies, and exercises should be communicated between nuclear powers (at present, communication is ad hoc or only partly realized through agreements such as the U.S.-Russia Agreement on Reciprocal Advance Notification of Major Strategic Exercises).

The NPT nuclear five have definite ideas, and in some cases longstanding disagreements, on the above.  But discussion on a possible nuclear code of conduct could usefully corral disparate conversations and provide a means to sustain discussion and debate in pursuit of narrowing or eliminating differences. The negotiation could leverage the idea (even if nominal) of NPT nuclear five solidarity to pursue a shared understanding of how, as the states invested with special responsibilities by the UN Charter and the NPT, they can address the lengthening shadow cast by the specter of nuclear crises today.

Some diplomats and officials across the nuclear five may argue that trying to negotiate a code of conduct (particularly given failed efforts to negotiate an outer space code of conduct) is a bridge too far in the present environment of NPT nuclear five division and animosity. On the flip side, supporters of the TPNW are likely to argue that negotiation of a code of conduct does not go far enough to address their concerns about nuclear risk. But the present state of affairs characterized by major power competition, fundamental disagreements between the nuclear states and backers of the TPNW, and a nuclear crisis in East Asia, is likely to continue fueling nuclear anxieties in foreign states (to include key U.S. allies) and increase nuclear risk. Successfully concluding a nuclear code of conduct between the NPT nuclear five is an ambitious endeavor, but even discussing such an agreement would be a positive development. At present, nuclear dialogues between the NPT nuclear five are infrequent, piecemeal, and sometimes lean on track 2 initiatives. While the latter are valuable, they are ultimately not a substitute for substantive discussions addressing nuclear risk – to include frank and difficult discussions about what the NPT nuclear five can do (and should not do) to reduce these risks.

The Benefits

These talks will not be easy. Russia and the United States, for example, warily eye each other and have significant and substantive disagreements regarding their nuclear forces and the role these forces play in national, regional, and international security. But even in the darker days of the Cold War, the two states worked out several agreements (such as the 1972 Incidents at Sea Agreement) focused on reducing the risk that their broader nuclear competition, and the practices, maneuvers, and frequent standoffs between their respective armed forces, would catalyze a nuclear crisis or conflagration.

Strategic differences should not obviate efforts to iron out the mechanics and mechanisms of reducing the risk of nuclear conflict.

A code of conduct dialogue, particularly one that sought to expand the military, scientific, and technical participation beyond past routine P5 meetings, could serve as an important channel for addressing nuclear challenges while also catalyzing new thinking – both within and between these states – about how their nuclear forces can play a stabilizing role within an increasingly unstable geopolitical environment. Moreover, discussions aimed at producing a common lexicon, a code of conduct, and potential side agreements that could emerge from these talks (such as agreements on improving communications to forestall nuclear crises), could provide critical building blocks toward future multilateral negotiations on nuclear force reductions that all NPT members have agreed to pursue. The next NPT nuclear five meeting should begin with a statement that nuclear risks are on the rise, that the five nuclear states have a responsibility to help reduce these risks, and that they will seek a new approach to foster a sustained dialogue between them that reflects a dedicated, sustained commitment to reducing the prospect of miscommunication, miscalculation, and nuclear war.

The NPT nuclear five are very unlikely to reach any grand bargains on their nuclear forces soon. But strategic differences should not obviate efforts to iron out the mechanics and mechanisms of reducing the risk of armed conflict, particularly nuclear conflict. There is widespread agreement that nuclear risks are too high but a lack of ideas regarding how to reduce them. The NPT nuclear five meeting to discuss a nuclear code of conduct could represent an early, but important, stepping stone in moving toward a less risky future.

The views expressed are solely those of the author and do not represent the views of the U.S. government, Department of Defense, or National Defense University.

  1. As the five states permitted to field nuclear forces are also the permanent members of the UN Security Council, they are sometimes referred to as the “permanent five” or “P-5.” As this designation expressly refers to their Council status rather than their NPT status (where, as noted above, they have agreed in principle to eventually eliminate their nuclear arsenals following future disarmament negotiations) this article will use the term “NPT nuclear five” rather than “permanent five.”
  2. In signing the treaty, these five states also pledged to “pursue” – together with other State Parties to the treaty – future multilateral “general and complete disarmament” talks.
  3. In 2015, for example, General Philip Breedlove, who at the time was Commander of U.S. European Command (and NATO’s Supreme Allied Commander for Europe) used this terminology in criticizing Russia for announcing that it was adding 40 intercontinental ballistic missiles to its nuclear force, stating “This is not a way that responsible nuclear nations behave … A rhetoric which ratchets up tensions in a nuclear sense is not a responsible behavior and we seek and ask that these (nuclear) nations handle this particular type of weapon in a more responsible way.” Reuters, “Russia not acting as a responsible nuclear power: NATO Commander,” 17 June 2015.
  4. Ronald Reagan, “Address Before a Joint Session of the Congress on the State of the Union,” 25 January 1984 and Governments of the United States and Soviet Union, “Joint Statement on the Soviet-United States Summit Meeting,” December 10, 1987. See also Alexey Arbatov, who advocates for current U.S. and Russian leaders to endorse this phrase: Alexey Arbatov, “Understanding the U.S.-Russia Nuclear Schism,” Survival 59.2: 33-66.
  5. ABC News, “’This Week’ Transcript:11-26-17: Sen. Tim Scott and Adm. Mike Mullen,” 26 November 2017.
  6. For the U.S. side, for example, a new effort could benefit from broader Department of Defense participation.