NUCLEAR WEAPONS ARE PROHIBITED
The entry into force of the Treaty on the Prohibition of Nuclear Weapons (TPNW) on January 22 prompted many comments from different quarters on the importance and significance of this new addition to positive international law. In accordance with its Article 15.1 the Treaty entered into force 90 days after the deposit of the 50th instrument of ratification. So far, 86 states signed and 52 have already ratified it.
Secretary-general Antonio Guterres hailed the Treaty as “an important step towards a world free of nuclear weapons”, and called on all countries “to work together to realize this vision, for our common security and collective safety”. Media in many parts of the world highlighted the fact that the TPNW is the first-ever instrument to ban all nuclear weapons and noted the strong opposition of the nuclear armed nations to it. Civil society organizations and public opinion in many countries, including those that possess atomic arsenals and their allies celebrated the entry into force as a historic step to rid the world of the last standing category of weapons of mass destruction. In an article for the Bulletin of Atomic Scientists dated January 22, former United States Secretary of Defense William Perry wrote: “The ban treaty rightly establishes abolition as the standard that all nations should be actively working to achieve, rather than an indeterminate future goal” and closed his powerful piece by saying that “America prides itself on being a nation of trailblazers; let us be the first nuclear-armed nation to blaze this new trail toward the top of the nuclear-free mountain”.
The same rationale that successfully supported and promoted the negotiation and adoption of the treaties that ban the other two categories of weapons of mass destruction – bacteriological (biological) and chemical  – certainly supports the prohibition of nuclear arms. There is a substantial difference between the partial prohibitions contained in Article II the Treaty on the Non-proliferation of Nuclear Weapons and the all-encompassing ban set forth by the TPNW, which applies to every Party, regardless of whether or not they possess nuclear weapons. Besides its distinct humanitarian approach, including the obligation of assistance to victims of nuclear tests – it reinforces the commitments already undertaken by non-nuclear states in previous instruments, such as the NPT, and sets forth the principle that nuclear weapons are not acceptable under the basic tenets that underpin civilized relations among nations. The Treaty constitutes a powerful normative and moral force against the development, manufacturing and stockpiling of nuclear weapons.
The TPNW is not directed against any state in particular nor does it advocate unilateral disarmament. States possessing nuclear weapons that join the Treaty will have to take action in accordance with Articles 1 and 4, which do not preclude concerted arrangements among possessor states to ensure mutual security during the disarmament process. In fact, nuclear-weapon States have negotiated among themselves in the past a number of ad hoc instruments aimed precisely at finding common ways to protect their security. The wealth of experience accumulated over decades of animosity and mistrust can be shifted to seeking security in the progressive reduction of nuclear weapons organically linked to their final elimination, rather than in the endless and fruitless pursuit of an elusive military and strategic superiority.
It is not reasonable to hide behind the possession of nuclear weapons by others in order to justify the perpetuation of one’s own. The possession of weapons that can wipe out civilization as we know it is simply not justifiable. If it were so, all nations would have valid reasons to acquire them. The often-repeated phrase that “we will keep nuclear weapons as long as they exist” is a self-serving expression of the unwillingness to even contemplate common-sense options to devise workable ways to achieve the stated objective of a world free of nuclear weapons. Nuclear disarmament would replace highhandedness and threats in international relations. Instead of obtuse, angry hostility to the TPNW, nuclear-weapon states would do better if they choose to engage constructively with the new treaty.
Several commentators have stressed the fact that a nuclear disarmament treaty that does not involve the existing nuclear weapon states is not effective. It is obvious that the TPNW will not be able to fully achieve its objective without the good-faith participation of those who actually possess nuclear weapons. It does, however, shift the focus from armed confrontation to the need for a broad consensus to address this existential issue. The states that extol the value of their nuclear armament have not been able to convince their own populations nor world public opinion that their security and that of the planet is better served by reliance on utter destruction in response to perceived threats. Polls across the globe, including in allies of nuclear-armed states, have shown that there would be strong popular support to effective, legally binding, verifiable and time-bound measures to completely eliminate nuclear weapons.
Voices from some quarters in nuclear-weapon states have argued that the pressure generated by the entry into force of the TPNW on states, agencies and vested interests that enable the development, research and production will only be felt in countries with well-established democratic institutions, where public opinion is able to influence the behavior of governments and other actors. This is only half true: in all societies the public has found ways of making its aspirations to be translated into action. Opinions, attitudes and beliefs have always been able to permeate barriers erected by autocratic and oppressive regimes, as the history of the world clearly shows. International law applies erga omnes, regardless of political systems. Internal pressures do not stem only from civil society: they also come from public pronouncements or private demarches by other states, as well as from international organizations, from positions taken by eminent personalities and from the general strength of public conscience. As frustration with the senseless armaments race and with lack of progress grows support of public opinion everywhere for effective measures of nuclear disarmament will also grow.
All members of the 51-year old Treaty on the Non-proliferation of Nuclear Weapons (NPT) are committed to its Preamble, which declares the intention to achieve at the earliest date effective measures in the direction of nuclear disarmament, and particularly to its Article VI to “pursue negotiations in good faith on effective measures related to the cessation of the nuclear arms race at an early date and to nuclear disarmament”. The 122 states that negotiated and adopted the Treaty on the Prohibition of Nuclear Weapons have given the example by doing exactly that. Their effort should be commended and followed rather that dismissed or ignored, so that the complete elimination of nuclear weapons is finally achieved.
Parties to the NPT – widely considered as “the cornerstone of the nuclear disarmament and non-proliferation regime” – must not allow the continued flouting of nuclear disarmament obligations. They must avail themselves of the opportunity offered by the forthcoming NPT Review Conference to recognize the valuable contribution of the TPNW to the important and urgent task of ridding the world from the threat of nuclear weapons and to agree on effective action in that regard. With its entry into force, the TPNW has now become an indispensable part of this endeavor.
President of Pugwash Conferences on
Science and World Affairs. Former United Nations
High Representative for Disarmament Affairs
 Bacteriological (biological) and chemical weapons were prohibited by multilateral treaties respectively in 1972 and in 1997.