Defence Minister Richard Marles has announced that Japanese shipbuilder Mitsubishi Heavy Industries has been awarded a massive contract to build three new frigates for Australia’s navy. The deal is worth a reported A$10 billion.

There are two reasons this deal is so significant.

The first is it enhances our naval capabilities. This is the first government in at least the past 50 years to push through such a significant expansion of Australia’s surface combatant fleet (meaning frigates and destroyers).

Under the government’s plans, we will be operating at least 20 surface combatants by the 2040s.

The second reason it’s so significant is because of what it says about our relationship with Japan.

Our strategic relationship has clearly evolved over the past ten years. In 2022, our two nations signed a joint declaration on security cooperation, which can be read as a quasi-alliance.

Now, this decision to purchase the new Mogami-class frigates really shows how much we trust Japan in terms of its industrial capability and its ability to support our........

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