Research advances mean that the time is ripe to ratify the ban on testing nuclear weapons.
This year marks the twentieth anniversary of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) agreement, so the timing of the latest nuclear blast from North Korea is pertinent. The country’s continued testing — this is its fourth test since 2006 — puts it on a path to developing miniaturized warheads that could be placed on missiles, risking an arms race in the region and increased global instability.
North Korea is one reason why the CTBT is not yet in force. The dictatorship is one of eight nuclear-capable nations that have yet to ratify the agreement, along with China, Egypt, India, Iran, Israel, Pakistan and the United States.
Science may seem to have little leverage in the volatile mixture of global power struggles and regional stand-offs, but it has been successful before. A major reason that so many countries were willing to sign up to the treaty in 1996 was the diligent research by a group of international scientists — known as the Group of Scientific Experts — established 20 years earlier in 1976. It had drawn up a credible road map of what technologies would be needed to verify that no country could cheat on its treaty obligations by carrying out undetected tests, thus giving them a military edge on those who abided by the rules.
Scientists can help again now — not least by explaining to politicians that the United States’ principal technical objections to ratification have been overcome. In 1999, the US Senate rejected then-president Bill Clinton’s push for ratification by a 51–48 vote, with opponents unconvinced that the technology was ripe either to detect cheaters, or to ensure the reliability and safety of the vast existing US stockpile of nuclear weapons without explosive testing.
Given the intensity of partisan politics in Washington DC today, hopes of any renewed effort by the United States to ratify the CTBT might seem fanciful. But at a symposium organized by the US Department of Energy in October 2015, US Secretary of State John Kerry called for just that, saying that the administration was determined to “reopen and re-energize the conversation about the treaty”.
Backing the case for ratification at the symposium were leading government scientists, such as US energy secretary Ernest Moniz — who had a key role in brokering the deal between the West and Iran over that country’s nuclear programme last July — and the heads of US nuclear-weapons labs at the Lawrence Livermore, Los Alamos and Sandia National Laboratories.
Kerry and the scientists pointed out that advances in research meant that the Senate’s concerns from 1999 are no longer relevant. The detection within minutes of last week’s nuclear test by North Korea once again demonstrates that the International Monitoring System of the Vienna-based Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization is up to the job it was designed to do. The US Stockpile Stewardship Program for its nuclear weapons, established in 1995, has also shown that advances in computer simulations and other technologies can assure the safety and reliability of its stockpile without any nuclear testing.
Although the CTBT has yet to enter into force, it has set an international standard. With the exception of North Korea, all countries have refrained from nuclear testing since 1998, when India and Pakistan each carried out two nuclear tests.
The United States has an opportunity to show leadership. By ratifying the CTBT, it would put huge pressure on China, India, Pakistan and other countries to do likewise. Iran, having scored a major diplomatic success with its nuclear deal with six world powers, is also in a strong position to support ratification. That would leave the signature of North Korea, probably the most recalcitrant non-signatory, for the CTBT to be able to enter into force. But as the Iran deal and the Paris climate negotiations show, diplomacy can prevail in the most difficult circumstances.
The CTBT alone will not solve all the complex issues of possession of nuclear weapons — in particular the disingenuous refusal of nuclear-weapons states to respect their commitment to the 1970 Nuclear Non-Proliferation Treaty to make serious efforts to disarm. But ratification of the CTBT would be a crowning achievement for science-based evidence and diplomacy in nuclear disarmament. Scientists played a key part in underpinning the nuclear deal with Iran; they now need to help to convince politicians that the CTBT is another deal in the best interests of international security.
Related links in Nature Research
Related external links
About this article
Cite this article
A secure future. Nature 529, 127–128 (2016). https://doi.org/10.1038/529127b