Members of the Lebanese Civil Defence inspect a damaged building after an Israeli strike on Beirut's southern suburbs, following renewed hostilities between Hezbollah and Israel amid the US-Israeli conflict with Iran. Lebanon, 9 March 2026. Picture taken with a mobile phone. REUTERS/Stringer

Rather than focusing on his long-overdue promise to end the war in Ukraine or relieving the suffering in Gaza, US President Donald Trump has opened yet another warfront, and with devastating consequences. With US and Israeli forces striking thousands of targets across Iran, international rules governing the use of force are under ever more serious threat.

The US-Israel military campaign against Iran, ‘Operation Epic Fury’, has escalated into a multi-front conflict, killing Iran’s Supreme Leader, Ayatollah Ali Khamenei, and drawing retaliatory strikes across the Middle East. The war is sending out shockwaves with significant implications globally, exacerbating the existing strains from long-running conflicts in Gaza and Ukraine, disputes over US tariff policies and the extrajudicial capture of Venezuela’s leader, Nicolás Maduro.

Despite reported progress in diplomatic talks between the US and Iran, on 28 February, four days after the fourth anniversary of Russia’s invasion of Ukraine, President Trump authorised strikes on Iran under a shifting litany of justifications, which had started with a vow to help Iranian protestors.

In the days that followed, the rationale rapidly expanded to include regime change, the dismantling of Tehran’s nuclear facilities, eradicating its ballistic missile programme and eliminating proxy networks. Finally, US officials settled on another core set of justifications including pre-empting an imminent attack on the US and avenging vague Iranian plans to assassinate Trump, while also tapping into historical grievances dating back to the 1979 hostage crisis. On 2 March, US Secretary of State Marco Rubio expanded the list further still by claiming that Israel had already decided to attack regardless – Washington feared retaliation from Tehran and felt compelled to intervene.

A doctrine of disruption

This cascade of shifting justifications came to exemplify the overreaching chaotic policy carried out under Trump largely outside the guardrails of both domestic safeguards and international law. The war on Iran follows disruptive diplomatic maneuvers by the US elsewhere, from a punitive maritime blockade of Cuba to an abrasive pursuit of a territorial acquisition of Greenland that has blindsided European allies.

At home, President Trump’s supporters sought to work outside domestic checks and balances, creating several instances of confusion. Speaker of the House Mike Johnson, for example, initially stated that Iran has ‘declared war on us’ while simultaneously insisting that ‘we’re not at war right now’. He later said it was not exactly a war but rather a ‘very specific, clear mission’ that does not require congressional authorisation under the War Powers Act.

This has translated into sweeping operations by Israel and the US on the ground. In just the first week, they had hit over 3,000 targets, including military command centres, nuclear sites, industrial zones, Payam airport and major cities. Iran has reported hundreds dead, including 48 senior officials who were killed in the opening salvo alone. At least 165 schoolgirls were killed in strikes on the war’s second day in the southern city of Minab. Missiles also struck Tehran’s Gandhi and Khatam al-Anbia hospitals, adding to the mounting civilian death toll.

The Iranian response has been far-reaching too, raining down missiles and drones on Israel and US assets in the Gulf, striking Dubai, Abu Dhabi, Doha, Manama and Riyadh. Explosions rocked US embassies and bases, killing six American troops in Kuwait.

In Lebanon, Israel struck south of Beirut and ordered a mass evacuation. In a sign of the deepening humanitarian crisis, thousands have begun fleeing across the Syrian border. Troops are now positioning for a major ground incursion. Tension has also spread to Turkey – which intercepted a missile heading towards its territory – and to Azerbaijan, which reported direct strikes on its territory and a massive mobilisation of troops along the southern border in response.

So far, the economic fallout includes ships stranded in the Strait of Hormuz and potential energy price surges worldwide. For years, the six Gulf Cooperation Council members balanced security ties with Washington against openings to Tehran. These strikes have now shattered the region’s safe-haven image, exposing economies to a conflict they cannot easily withdraw from.

The US has also expanded the theatre of war to the Indian Ocean where a US submarine struck and sank the Iranian frigate IRIS Dena off Sri Lanka, killing at least 87 sailors – the first combat sinking of a warship by a US torpedo since 1945.

Gaza, a casualty yet again

The war is taking its toll on other crises, too. It has effectively paralysed the much-needed Gaza humanitarian aid effort. Citing ‘security adjustments’, Israel shuttered the Rafah crossing on 28 February, halting humanitarian aid and medical evacuations and reviving the spectre of famine. As Trump’s ‘Board of Peace’ reconstruction initiative stalls in Washington, the Netanyahu government has further seized the distraction to expand ‘Iron Wall’ operations in the West Bank, further entrenching the already displaced population of over 40,000 Palestinians.

As Washington’s focus fractures across the Caribbean, the Arctic and the Persian Gulf, Moscow’s position appears to have been bolstered. The Kremlin has offered to boost vital energy supplies for China and India as President Trump is set to ease sanctions on Russian oil. Peace talks are faltering over Russia’s demand for the full Donbas region, which Ukrainian President Volodymyr Zelensky rejects. Ukraine has reclaimed some territory this winter and preserved its energy grid despite a record 288 Russian missile strikes in February alone.

Despite the far-reaching repercussions, some diplomatic responses have been surprisingly muted and unwilling to challenge the legality of the campaign. German Chancellor Friedrich Merz refused to ‘lecture’ partners on international law, effectively endorsing a regime-change mandate. Belgian Minister of Foreign Affairs Maxime Prévot offered a legal paradox, calling the strikes a breach of international law yet justified for security at the same time. Meanwhile, Canadian Prime Minister Mark Carney initially backed the war as a means of curbing Iran’s nuclear capability and threat to peace and security, though he added days later that it was ‘with regret’ as the strikes appeared ‘inconsistent with international law’.

Law of the jungle

There have, however, been voices robustly defending international law and urging restraint. Spanish Prime Minister Pedro Sánchez denounced the strikes as an ‘unjustified, dangerous military intervention’ outside international law. Malaysian Prime Minister Anwar Ibrahim has called the operation a ‘vile attempt’ to derail regional negotiations. Norway’s foreign minister declared the strikes to be a violation of international law. China called for an immediate halt, with Foreign Minister Wang Yi warning that the world cannot return ‘to the law of the jungle’. Russia’s foreign minister called the strikes a ‘dangerous adventure’.

Religious leaders have also spoken out. Pope Leo XIV appealed for an end to ‘a spiral of violence’. Ahmed Al-Tayyeb, the Grand Imam of Al-Azhar, one of Sunni Islam’s most influential voices, urged the states involved to engage in dialogue.

In a statement on 4 March, a group of UN experts warned that the attacks were likely to cause the ‘arbitrary displacement of thousands’ and said the attacks violated international law as well as the duty to peacefully settle disputes under Article 2 of the UN Charter. UN High Commissioner for Human Rights Volker Türk urged those involved to take immediate steps to de-escalate to prevent further devastation for civilians. ‘The crisis in the Middle East […] has been spreading like wildfire […] The world urgently needs to see steps to contain and extinguish this blaze,’ he said.

While Washington insists these strikes address a core regional threat, unilateral action without consensus risks a permanent cycle of instability. This ‘Epic Fury’ era enables leaders like Israeli Prime Minister Benjamin Netanyahu and Russian President Vladimir Putin, and now increasingly President Trump, to flout international norms with near impunity.

‘President Trump appears not to care very much about the international legal regime governing the use of force,’ says Allen Weiner, Professor of International Law at Stanford Law School. ‘One can expect that if the United States, which was perhaps the leading architect of the UN Charter’s regime on the use of force, decides that states can go to war whenever they perceive it to be in their interest, other states will do so, as well.’

Weiner tells Global Insight that the future of the post-Second World War international legal order is at a tipping point. He argues that the future of the UN Charter depends on global condemnation, costs for aggressors and the ideologies of future leaders. ‘The great question is whether the current disregard for international law demonstrated by powerful states will bring about lasting change, or whether this is a temporary moment,’ he says.

Emad Mekay is a freelance journalist and can be contacted at emad.mekay@int-bar.org