The risk of nuclear war does not rest on a single decision. It accumulates, test by test, each explosion
edging the world closer to potenƟal catastrophe. That escalaƟon carries a cost of its own, too: every
nuclear weapon test leaves a scar on land and on water, and some who lived near test sites have
carried that cost for generaƟons, long aŌer the tesƟng itself ended. The InternaƟonal Day against
Nuclear Tests, IDANT, exists because those dangers remain part of our shared history, and because
governments sƟll face the same choice every year.
There was a Ɵme when the ground shook oŌen. For four decades, the test site at SemipalaƟnsk was
one of the places that felt it most, unƟl its closure 35 years ago silenced a stretch of the Kazakh
steppe. That decision reflected a broader shiŌ away from nuclear tesƟng. In the years before the
Comprehensive Nuclear-Test-Ban Treaty, the CTBT, opened for signature in 1996, more than 2,000
such explosions were carried out. Since, fewer than a dozen. That the tremors grew rare is not an
accident of history. It is a choice, made and remade by governments every year, and unlike a fact, a
choice can be unmade. It must not be.
That choice is something built, maintained and verified, too. At the heart of it sits a global network of
over 300 staƟons and laboratories, spread across more than 90 countries, that listens to the earth
with extraordinary precision. The InternaƟonal Monitoring System, established under the treaty’s
verificaƟon regime, can detect an explosion equivalent to 500 tonnes of TNT, roughly three per cent
of the Hiroshima yield. Every declared test by the DemocraƟc People’s Republic of Korea was
detected, including the smallest. The system does not ask the world to trust. It gives the world a way
to check.
Science, in this sense, is the anƟdote to suspicion. It allows states to act with confidence that
commitments are being upheld, and to see that others are doing the same.
None of this stands alone. The Treaty on the Non-ProliferaƟon of Nuclear Weapons, the nuclearweapon-free zones, and the CTBT itself are not abstracƟons. Together, they form the architecture of
global non-proliferaƟon and disarmament, the quiet scaffolding beneath internaƟonal peace and
security, and each has shaped how governments act for decades. But no treaty sustains itself. It holds
only because the states bound by it choose, year aŌer year, to be held by it.
That is the part of the story that cannot be taken for granted right now. Nuclear weapons are not a
problem any one country can solve alone. Their consequences would not stop at naƟonal borders,
and no state can contain those risks by itself. A world free from nuclear tesƟng cannot be built
piecemeal. It depends on shared commitments and on the willingness of every state, including those
that possess nuclear weapons, to sustain the systems that make trust between them possible.
I say this because some governments are speaking, more openly than they have in years, about the
possibility of tesƟng again. That is precisely the issue IDANT seeks to address: what are we doing,
together, right now, to ensure the world does not slide back towards nuclear tesƟng, this year or any
year aŌer it?
I believe the answer has three parts. First, a direct call to the nine remaining Annex 2 states whose
raƟficaƟon the treaty needs to enter into force: act without delay. The CTBT’s full strength, legal and
moral, cannot be realised unƟl you do. Second, sustained support, in word and in funding, for theverificaƟon regime and the organisaƟon that keeps it running. An instrument this precise does not
maintain itself. Third, and the foundaƟon for both, a recogniƟon that the mulƟlateral system, the
Comprehensive Nuclear-Test-Ban Treaty OrganizaƟon and states themselves have to work in concert,
not in parallel, not in compeƟƟon. The tools for this are already available: dialogue, transparency and
pracƟcal steps that build confidence. What is required is the will to use them.
None of this is theoreƟcal. The agreements exist. The infrastructure exists. What they have achieved
so far is proof of what is possible when they are taken seriously.
The last 30 years were not inevitable. Neither are the next 30. That is not a warning. It is an
invitaƟon, to every government sƟll weighing what kind of world it wants to leave behind.
Restraint was chosen, on purpose. It must be chosen again, and again.
One treaty. One goal. Zero tests.
Robert Floyd is ExecuƟve Secretary of the Comprehensive Nuclear-Test-Ban Treaty OrganizaƟon.