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  • Writer's pictureStuart Jeffery

Common(wealth) Knowledge #18: Australia and international law - a nuclear history

Updated: Apr 7, 2023

Why international law means Australia doesn’t have nukes, but other countries do.

Recent setbacks for Russia in its war against Ukraine have led to concerns over Russian President Vladimir Putin’s apparent willingness to make the war nuclear. This would be the first time nukes have been deployed in war since their first use in World War II. In the background of this discussion, one question that some Australians have been asking is ‘why doesn’t Australia have nukes?’

The first reason behind Australia’s lack of nuclear capabilities is a geopolitical one. Since the creation of the ANZUS Treaty in 1951, the United States has guaranteed Australia’s independence by pledging to come to the defence of Australia if Australia was attacked. Australia’s relationship with its nuclear ‘Big Brother’ means that Australia doesn’t need to spend time and money developing its nuclear capabilities, and the ongoing cost of maintaining these capabilities.

The second, and more important, reason is the United Nation’s Treaty on the Non-Proliferation of Nuclear Weapons, more simply known as the Nuclear Non-Proliferation Treaty or NPT. Created in 1968, this treaty aims to stop the horizontal proliferation of nuclear weapons. Horizontal proliferation refers to non-nuclear powers becoming nuclear powers by developing those weapons, whereas vertical proliferation happens when existing nuclear powers increase the number and quality of their nukes.

It is often said that international law is ineffective because it relies on pacta sunt servunda, a Latin phrase meaning ‘agreements must be kept.’ The limited legal power of the UN to enforce treaties means that the UN relies on the good faith of treaty signatories to keep the treaty. The more countries that sign a treaty, the more it will be seen as a ‘norm’ of international law and global politics, making it harder for democratic nations, which rely on popular support at home, to break the treaty.

The voluntary nature of international treaties means that countries can withdraw from the NPT whenever they want. North Korea has withdrawn from the treaty, and Israel, Pakistan and India, all of whom have developed nuclear weapons relatively recently, never signed the treaty. It is for this reason that people often claim that international law doesn’t work, but this ignores the fact that most international law is followed most of the time. It’s just that when it is breached, it gets a lot more publicity, as the media won’t report on mundane topics like international law not being broken.

Australia was one of the biggest proponents for the horizontal proliferation of the NPT, in particular because of the security threat posed at the time it was implemented, during the Vietnam War in the Cold War. However, if countries can withdraw from international treaties, then why can’t Australia?

Liberal democratic governments, unlike authoritarian regimes in countries like North Korea, need to maintain their popularity with the voters at home. When something like the non-proliferation of nuclear weapons, at least horizontally, becomes an accepted international norm that applies to everyone, then withdrawing from a treaty would hurt both the government’s popularity at home and the country’s reputation internationally. Unless the domestic opposition also supports withdrawal from the treaty, they would likely use the withdrawal at the next election to be elected, and then promptly ratify the treaty again.

It was once assumed that the executive branch of government in Commonwealth nations like the United Kingdom and Australia had the authority to withdraw from treaties on its own and on behalf of the country’s government. This was derived from the ‘prerogative power’ of the Crown, vested in the Governor-General. This power is independent of Parliament, instead coming from the historical powers of the monarch, alongside the powers of declaring war and suing for peace.

However, that assumption was put to bed in R (Miller) v Secretary of State for Exiting the European Union [2017]. In that case, the Supreme Court of the United Kingdom ruled that the Executive, specifically the named Secretary of State, did not have the power to withdraw from the Treaty on European Union, which would allow the UK to leave the EU. Instead, the court concluded that this required a law to be passed by Parliament. Absent any contradictory ruling from the High Court of Australia, it can be assumed that this ruling would be upheld in Australia too.

Therefore, even if the Australian government wanted to withdraw from the NPT, which is unlikely given that Australia does not want to risk undermining the international norm that it creates, which may lead to other countries withdrawing and building nukes, the domestic political consequences would be significant. It may even cause the government to lose the next election, adding just another incentive to follow international law. And this is why international law is generally more effective at compelling liberal democracies to comply with it, as opposed to other types of government.

Stuart Jeffery is a freelance researcher & digital editor for 6 News. His views on personal social media pages are his & his only, and do not reflect the views of 6 News or our journalists. He abides by 6 News' editorial standards relating to fairness & accuracy.

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Treaty on European Union, opened for signature 7 February 1992, [2009] OJ C 115/13 (entered into force 1 November 1993).

Treaty on the Non-Proliferation of Nuclear Weapons, opened for signature 1 July 1968, 729 UNTS 161 (entered into force 5 March 1970).


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