If there's one area of New Zealand foreign policy that demands delicate diplomatic language from elected officials, it is the country's nuclear-free status.
So when Defence Minister Chris Penk suggested it "would be helpful" to have a conversation about the difference between nuclear weapons and nuclear propulsion, the response was swift.
Opposition parties questioned whether the government was planning a review of the relevant legislation , forcing Prime Minister Christopher Luxon to confirm there would be no change to the policy .
Unfortunately, the issue may not be that easy to avoid in the near future.
Penk was speaking at a security forum in Singapore and responding to a reporter's query about what Australia's acquisition of nuclear-powered submarines might mean for nuclear-free New Zealand.
That's a fair question, given Australia is New Zealand's only formal ally, and closer military relations between the two countries are central to the government's Defence Capability Plan .
The AUKUS factor
Penk's comments were also timed unfortunately, coming a day after United States Secretary of War Pete Hegseth suggested New Zealand was " freeloading " as an ally, and defence spending at 2% of gross domestic product (GDP) was "not enough".
This tacit pressure comes at a time when global military expenditure has accelerated rapidly, wars and conflicts are expanding, and fears grow about a new arms race .
Hegseth is pushing for partner nations to "reach a level where 3.5% of national spending goes towards their own military".
That reflects the recent commitment by NATO countries to invest 5% of GDP annually on defence and security by 2035 (with 3.5% on core military requirements).
New Zealand and Australia are not members, but both have partnership agreements with NATO. Australia currently spends 2.2% of its GDP on the military, and is aiming for 3% by 2033.
New Zealand aims to hit the 2% target in 2032, which would bring spending broadly in line with peacetime military budgets over the past century . Whether that will be enough, however, is a key question - especially as advances in military technology gather pace.
For example, AUKUS partners are about to begin cooperating on the first "Pillar II" initiative, the development of autonomous undersea drone systems . New Zealand is still officially weighing up Pillar II membership, although many of the practical steps required seem to be already underway , and the price of entry to this club will be expensive.
Even outside AUKUS, New Zealand faces a steep bill to replace its ageing navy frigates . While these vessels could supplement Australia's purchase of 11 new frigates and create efficiencies in the process, it would still stretch spending well beyond the 2% of GDP target.
Undermining nuclear-free law
There's a wider perspective needed, too. Hegseth's criticisms must be seen in the context of his administration's undermining of the international rules-based order central to New Zealand foreign policy.
Any suggestion by a cabinet minister - however vaguely phrased or subsequently rejected by the prime minister - that part of the nuclear free policy might be on the negotiating table becomes doubly sensitive.
The Nuclear Free Zone, Disarmament, and Arms Control Act prohibits the acquisition, testing or stationing of nuclear weapons in New Zealand. It also bans "entry into the internal waters […] by any ship whose propulsion is wholly or partly dependent on nuclear power".
That means foreign vessels retain freedom of navigation rights, in accordance with international law, for peaceful transit through New Zealand's territorial waters - but they can't land.
Chipping away at part of the comprehensive anti-nuclear policy would undermine the overall purpose of the law:
to promote and encourage an active and effective contribution by New Zealand to the essential process of disarmament and international arms control.
New Zealand's commitment to increase military spending should therefore be matched by support for initiatives that seek to reboot arms control, reduce the risk of wars being triggered accidentally and to regulate military use of artificial intelligence .
As even the major nuclear powers concede, any future war between them cannot be won . For a small power such as New Zealand, working to prevent such a catastrophe is the more important objective.
Alexander Gillespie does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
