The Iranian diaspora has been celebrating and governments around the world have generally not mourned the death of Ayatollah Ali Khamenei in last weekend’s US and Israeli air strikes on Iran.While there has been much political justification for these attacks from Washington and Jerusalem, neither has sought to legally justify their conduct. No real effort has been made to reference the acknowledged right of self-defence, most likely because the evidence for invoking self-defence did not exist. In other words, there was no prospect of Iran launching an imminent attack.Inevitably, the legal basis for the original missile attack on Iran will become a minor detail as the conflict develops. Nevertheless, what occurred on February 28 will remain important. Lawyers place great emphasis on precedent, and international lawyers particularly look to state practice in interpreting how international law actually operates, which can evolve over time. This allows the interpretation of international law to account for new developments, such as military force and cyber attacks. This evolution is particularly important because international law is principally contained in, and associated with, the 1945 United Nations Charter. This means it is more than 80 years old. Australia’s approach to force and the lawAustralia has generally been prepared to adopt an evolutionary approach towards how force can be used consistently with international law. In the wake of the September 11 terrorist attacks on the United States, for example, Australia accepted the US could exercise self-defence. So Australia supported the US’ retaliatory attacks on Afghanistan and joined “Operation Enduring Freedom”. Similarly, the Australian government supported Israel acting in self-defence following the 2023 Hamas attacks.Australia was more cautious with using force to militarily disarm Iraq in 2003. While it ultimately joined with the US and United Kingdom in “Operation Iraqi Freedom”, it only did so following an extensive public and political debate in Australia. This included the publication of the Howard government’s legal advice justifying military intervention. With respect to the 2022 Russian invasion of Ukraine, Australia has taken a much clearer position, pointing out the illegality of that conduct. It has joined more than 20 other countries in the International Court of Justice asserting there was no legal basis for Russia’s actions.On January 3 2026, the US military intervened in Venezuela, resulting in the arrest and detention of President Nicolás Maduro and his wife on US narco-terrorism and related drug-trafficking charges. Since then, the Trump administration has engaged in a breathtaking array of international conduct, raising multiple significant international law issues. This includes:the threat to use military force to seize Greenlandthe threatened imposition of significant tariffs against six European countries in response to debates over Greenland’s futurecreation of the “Board of Peace”, initially focused on Gaza reconstruction but with a much larger global mandate potentially rivalling the United Nationsthe seizure of vessels on the high seas linked to Venezuela and Iranthe Iranian missile strikes and a strategy targeting the Iranian leadership.For longstanding allies such as Australia, this conduct by the Trump administration creates a significant challenge. This is especially so when seen against the backdrop of the ANZUS alliance, and now increasingly through the lens of AUKUS. Australia has to date paid $1.6 billion to the US and committed a further $3.9 billion to Australian AUKUS ship-building facilities.The ‘say nothing’ approachWhile Australia’s AUKUS future rests with the US and UK, what options does Canberra have in the face of the Trump administration’s approach to international law and international relations? It can either say nothing, or say something.All the statements made to date by Albanese government regarding the legality of the US and Israeli conduct have been in the “say nothing” category. At most, the Albanese government has said any legal justification needs to be made by the US and Israel. To say something with respect to international law would require a clear statement that indicated Australia’s position. Norway’s Prime Minister Jonas Gahr Støre, for example, issued a statement following the military strikes asserting that: “The attacks this morning and the spreading of the conflict to Iran’s neighbouring countries is not in line with international law.” It should be acknowledged that it would be exceptional for Canberra to issue a unilateral statement such as this on a matter in which Australia was not directly involved. However, in these matters, the Albanese government has a record of acting together with so called “like-minded” countries such as Canada and New Zealand. In 2024–25 the three countries issued joint statements on the Gaza conflict, outlining a shared position on international humanitarian law. Sometimes, though, Australia is prepared to chart a course that is separate from the US. For example, Australia has adopted a different position from the US and Israel with respect to the recognition of Palestine. It has moved towards conferring formal recognition along with Canada, France and the UK in September 2025. How the use of force is controlled and regulated is fundamental to international law and international relations. It goes to the very heart of the UN system. Australia has aspirations for a seat on the UN Security Council, commencing in 2029. It needs to make clear whether it supports the UN Charter or the “might is right” approach of the Trump administration.Donald Rothwell receives funding from Australian Research Council