Anzac Day 2026 arrives in tumultuous times: unresolved conflict in the Middle East, the erosion of the old international order, the famous Doomsday Clock set closer to midnight than ever before.

Without doubt, this brings New Zealand’s defence relationship with its closest neighbour (and only formal ally) Australia into sharp focus.

In March, not long after the initial attack on Iran by the United States and Israel, closer defence relations with Australia were formalised under the Anzac 2035 commitment.

This essentially sets out to “operationalise” previous statements on closer defence relations, and reaffirms the importance of the ANZUS alliance – which also marks its 75th anniversary this year.

Given ANZUS became virtually defunct after New Zealand’s nuclear-free declaration in the 1980s, this is a remarkable turnaround. The vexed question of joining the AUKUS security pact aside, Anzac 2035 aims for a more cohesive and integrated combat-capable force.

This Anzac Day, then, it’s worth putting these latest developments in context. And it is important to understand the risks, as well as the rewards, of closer defence ties with Australia.

Trans-Tasman military cooperation is often thought to start with Gallipoli in 1915. In fact, it predates that pivotal moment by more than half a century when........

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