As well as thousands of deaths, the consequences of the US President’s war on Iran include an energy crisis, economic shock and damage to the international legal order. Global Insight explores the implications, including for President Trump himself.

President Donald Trump’s surprise attack on Iran, carried out jointly with Israel on 28 February, killed Iran’s Supreme Leader Ayatollah Ali Khamenei, members of his family and approximately 40 senior government and military figures. The resulting conflict has had profound and far-reaching consequences.

Thousands of targets across Iran were hit by US and Israeli forces over the next 38 days. Iran struck back after the initial attack, targeting America’s allies in the Gulf region. A temporary ceasefire was reached and went into effect on 8 April. Trump administration officials say the US is continuing to negotiate with Iran, while the President has also warned that bombing could resume if these talks don’t produce results.

The war has triggered a global economic shock, with maritime restrictions in the Strait of Hormuz contributing to substantially higher energy prices worldwide. Before the war, about 20 per cent of the world’s oil and liquefied natural gas (LNG) supply passed through the strategic waterway.

Critics argue there was no clear evidence that Iran was close to assembling an atomic bomb. Iran’s nuclear facilities had already been heavily damaged by US and Israeli strikes in summer 2025, with underground stockpiles of enriched uranium buried beneath rubble.

President Trump faces a hard reckoning. Rather than forcing the Iranian government to capitulate in what the US President initially said would be a short conflict lasting only a few weeks, Trump’s actions have instead caused the largest global oil crisis in history.

‘Two forms of violence’

Meanwhile, over 90 million ordinary Iranians face repression and increasingly severe economic hardship. ‘The international discussion about Iran remains profoundly disconnected from the reality experienced by those living under the Islamic Republic,’ says Shiva Amiri, an officer of the IBA Human Rights Law Committee.

‘Much of the conversation continues to revolve around nuclear negotiations, sanctions, oil markets, regional escalation and the legality of military operations, while the people most affected by this crisis are too often reduced to the background of geopolitical analysis,’ says Amiri, who’s an Iranian-American legal scholar based in Toronto.

The Iranian government cracked down brutally on anti-regime protestors in January, killing as many as 5,000 civilians and arresting 25,000 more, according to the Human Rights Activists News Agency (HRANA), a US-based group focused on documenting conditions inside Iran. Those numbers could well be higher – obtaining precise figures is difficult because of the internet and communications blackout imposed by the government, which has inhibited the collection of reliable information from people inside Iran.

Amiri sees the conflict not simply in terms of regional security but as ‘a prolonged human protection crisis’ with global implications. While international attention has focused on the legality of US and Israeli military action, there has been insufficient scrutiny, she says, of the internal repression of civilians.

‘Even after the ceasefire, the regime’s war against its own population has not ended,’ she says, pointing to reports of executions, arrests and intimidation of lawyers, journalists and dissidents. ‘The blackout is not merely censorship. It is a mechanism of control. It suppresses evidence, isolates victims, obstructs documentation and creates conditions in which abuses can occur without scrutiny.’

The harm from US-Israeli attacks on people and civilian infrastructure in Iran has been significant. More than 3,000 people were killed in Iran between 28 February and 8 April. Of those, 1,700 were civilians including 300 children, according to HRANA. ‘The population is trapped between two forms of violence; internal repression on one side and military escalation on the other,’ says Amiri.

Economic destruction

More broadly, the Iran war has caused widespread economic damage around the world. As of mid-May, shipping through the Strait of Hormuz had been severely restricted for more than 75 days with very few vessels getting through. Iran has allowed passage for a small number of tankers on a case-by-case basis, notably for Iraqi exports and Chinese imports. In April, the US began attempting to block maritime traffic entering and exiting Iranian ports.

In March, oil prices increased significantly and the International Energy Agency (IEA) coordinated the largest ever multinational release of strategic petroleum reserves of more than 400 million barrels of crude oil. As of mid-May, cumulative supply losses from Gulf producers had exceeded one billion barrels, the IEA reported. Global oil inventories are being depleted at a record pace.

‘The volatility, the turbulence, the fluctuation, just the added uncertainty in the market is rattling all of our clients, both in the agrochemical and industrial chemical communities,’ says Lynn Bergeson, a member of the IBA Agriculture and Food Section Advisory Board. ‘The market impacts are nascent, but they will become more severe and adverse commercially as the year progresses.’

France, Germany and the UK have offered tax cuts and aid packages to help blunt the impact of rising fuel costs. Indeed, the Iran war has accelerated a profound shift already underway inside Europe, away from reliance on the US and towards a posture of strategic independence.

The conflict has exposed Europe’s vulnerability to external energy shocks in ways not seen in decades. The disruption of oil, gas and petrochemical supplies from the Gulf is forcing policymakers in Brussels to contemplate measures once considered unthinkable in peacetime. ‘It’s creating a lot of stress around the supply of energy products,’ says Yves Melin, Co-Chair of the IBA International Trade and Customs Law Committee.

‘The EU is now looking at trying to map what energy products we have available and how we could ration them and place them at the disposal of strategic industry,’ says Melin, a partner at Cattwyk, a trade law firm in Brussels. ‘This is really showing that Europe is not going to be safe until it generates its own energy.’ If the crisis persists, the EU could face an energy shortfall approaching ten per cent of what’s needed, with consequences spreading far beyond fuel markets into agriculture, chemicals and manufacturing supply chains, says Melin.

The result will probably be an acceleration of Europe’s push toward strategic autonomy. And the continent’s strategic recalibration now extends well beyond trade into defence, industrial planning and geopolitical alignment. ‘Trade policy is becoming security policy,’ says Melin. Sourcing decisions involving steel, rare earth minerals, drone components and energy infrastructure are increasingly viewed through a national security lens.

Melin adds that the crisis will ‘turbocharge’ the EU’s efforts to expand renewable and nuclear energy generation in order to reduce dependence on foreign hydrocarbons. ‘This conflict is putting all of those policies on steroids,’ he says.

The great recalibration

Disruption of the vital oil trade through the Strait of Hormuz has revealed deep structural vulnerabilities that extend far beyond hydrocarbons, says Raj Bhala, an officer of the IBA International Trade and Customs Law Committee. ‘This war is a lesson for all consumers and producers on the importance of oil and natural gas in supply chains of products that we might never have even imagined would be affected,’ says Bhala, University Distinguished Professor at the University of Kansas Law School. Costs are increasing globally for items as varied as dental floss, food packaging and beer cans. ‘Almost every product in the Harmonized Tariff Schedule of the US is affected either directly or indirectly by oil and LNG constraints,’ Bhala says. ‘Consumers are feeling it in the stores. You can see price rises.’

Beyond the immediate price pressures, a more profound impact is found in how businesses and governments now perceive geopolitical risk, not only in the Middle East, but globally. ‘It’s a deeper shock,’ Bhala says. ‘No longer can exporters and importers take it for granted that choke points will remain open, and no longer can they conduct business as usual without thinking about alternative sources of supply.’ To put it bluntly, he adds, ‘this is a stimulus, a catalyst to diversifying your supply chain away from the Middle East.’

Presuming the conflict continues, Gulf states will face further disruption in aviation and financial services networks, amid the rerouting of airline flights and a growing reluctance by companies to station employees in certain countries in the region due to the security risks.

‘My focus as a disputes lawyer is business and how developments impact on the objectives of clients,’ she says. ‘Commercial activity is closely tied to predictability, continuity and confidence in the operating environment, all of which are important considerations for investors.’ Despite the challenges posed by the conflict, however, Aranjo says there are reasons to believe the region will recover quickly and continue to demonstrate economic resilience, social cohesion and commercial strength.

Looking ahead, Bhala believes that the combined effect of war, sanctions and trade fragmentation won’t be temporary. He sees a long-term structural shift in global economic organisation in which supply chains, trade relationships and legal norms are permanently recalibrated around geopolitical risk rather than efficiency or comparative advantage. ‘We are in a situation where it’s not really about law anymore, but about geopolitical power and who gets to decide,’ Bhala says.

A key driver of that shift is the unravelling of the post-Second World War international order and the weakening of multilateral institutions. Coercion increasingly replaces legal constraint, and the Trump administration faces serious questions about whether the US attack was justified – with most international trade and human rights experts believing it was not.

‘Bridges next, then Electric Power Plants!’

After the Vietnam War and the Pentagon’s attempted cover-up of the Mỹ Lai village massacre by US Army troops, the American military invested in training service members in the laws of armed conflict. Now, the Iran conflict creates a dangerous disconnect between the professional military and civilian political leadership in Washington, says David Crane, a former US Army lawyer and founding Chief Prosecutor of the Special Court for Sierra Leone. ‘We have an educated force that understands the laws of armed conflict and what their obligations are under international law,’ Crane says. ‘But yet we have a national command authority that is ignoring the whole process of using law on the battlefield.’

A month after the conflict began, President Trump gave a nationally televised speech in which he said that the US was ‘going to hit [Iran] extremely hard over the next two to three weeks, we’re going to bring them back to the stone ages, where they belong.’ In a social media post a few days later, President Trump then declared that ‘[the US] Military, the greatest and most powerful (by far!) anywhere in the World, hasn’t even started destroying what’s left in Iran. Bridges next, then Electric Power Plants!’

Apparently seeking to raise pressure on Iran to meet a US ultimatum, President Trump said on 7 April that ‘a whole civilization will die tonight, never to be brought back again. I don’t want that to happen, but it probably will.’

Such public statements by the US President, echoed by high-ranking officials, risk creating ‘international criminal liability’ under doctrines relating to aggression and unlawful targeting, Crane says.

Even if frontline US forces are attempting to avoid civilian casualties and comply with targeting rules – as would be expected – legal exposure extends to senior civilian and military leaders involved in authorising the conflict. Knowingly carrying out illegal orders could also expose individual service members to criminal liability. ‘A soldier, airman or marine cannot follow unlawful orders and is obligated to tell that superior that it is an unlawful order,’ says Crane, who has been an advocate for holding Russian soldiers accountable for war crimes committed in Ukraine.

The reckoning ahead

The path to meaningful international accountability for President Trump and his aides would be a difficult one, however, because neither the US nor Iran is party to the International Criminal Court (ICC), and any referral through the UN Security Council would almost certainly be blocked by a US veto. ‘From a practical point of view, there’s no international accountability unless the world creates a special tribunal,’ Crane says.

Since the Nuremberg and Tokyo trials conducted after the Second World War, the UN and groups of nations have created special tribunals to address specific war crimes in the Balkans, Rwanda, Sierra Leone, East Timor and Chad. There have also been a number of war crimes and atrocity cases brought under universal jurisdiction. This is the principle whereby a state prosecutes serious international crimes even though they happened abroad. ‘What we’re seeing unfold today could at some point several years down the road result in some sort of proceedings against a former president of the United States,’ says Leila Sadat, a professor of international criminal law at Washington University Law School in St Louis.

‘The Trump administration has shown a reckless disregard for the laws and customs of war,’ adds Sadat, who has served as a special adviser on crimes against humanity to the ICC and is a former member of the IBA War Crimes Committee Advisory Board. ‘There’s a pattern that shows a reckless disregard for the principle of distinction, of the requirement that you take all reasonable precautions to make sure civilians are not harmed.’

In the US, the conflict has intensified long-running trends toward executive unilateralism and congressional weakness, particularly in the area of war powers, says James Thurber, Founder of the Center for Congressional and Presidential Studies at American University. ‘The war accelerates an attack on our democratic institutions,’ he says, pointing to Trump’s expansion of presidential authority through executive orders, unilateral trade actions and military operations.

The Trump administration has taken executive power to an unprecedented level, particularly in bypassing Congress to unleash what the President called ‘major combat operations’ against Iran, Thurber says. ‘Congress for years has not really used the War Powers Act the way it could be used,’ he adds. ‘When institutions are weakened, it’s easy to backslide even more.’

Under the War Powers Act, once the president introduces US forces into hostilities, the military action must end within 60 days unless Congress authorises or extends the deadline. President Trump has now told Congress that, as a result of the ceasefire that began in April, he doesn’t need its authorisation for US military operations in Iran. The Trump administration has also referred to the War Powers Act as ‘unconstitutional’.

The erosion of institutional checks inside government has also enfeebled policy-making itself, particularly within the national security apparatus. Early in the second Trump administration, Hegseth fired the top lawyers in the Army, Navy and Air Force, describing them as potential ‘roadblocks to orders that are given by a commander in chief’. That meant the departure of career civil servants and military professionals who traditionally provide internal dissent and alternative policy analysis. ‘The people that would have stood up to Trump are gone,’ Thurber says.

This had implications for the planning by President Trump’s team around the economic and geopolitical risks associated with escalation in the Gulf. Military leaders reportedly warned Trump that a strike could lead Iran to threaten shipping through the Strait of Hormuz, but the President believed Tehran would capitulate first and that any disruption could be handled by the US military.

Now, the Trump administration’s great vulnerability lies in the war’s impact on US inflation and household costs. High fuel prices will probably dominate voter concerns heading into the US midterm elections in November. His domestic opposition can be expected to focus on the economic pain of the price of gas and the rising affordability crisis now eroding middle-class living standards. ‘Trump can say everything’s great, but if people are looking every day at gas station signs that say $4.50 a gallon or more, it’s a reminder of the consequences of the war,’ Thurber says.

At the same time, the war is dividing President Trump’s political base, particularly among those opposed to open-ended foreign military intervention. If Democrats regain control of the House of Representatives, aggressive oversight investigations into Trump and Hegseth’s conduct of the war are expected.

Collapse of restraint

From a legal standpoint, the central issue remains the legitimacy of the war itself. The US has departed from the framework established after 1945, in which disputes were to be resolved peacefully except in narrow circumstances involving self-defence or where UN Security Council authorisation has been established. ‘The unilateral use of force by a Member State of the UN is an act of aggression. It violates the UN Charter. It violates international law,’ says Crane. ‘We are no longer under the UN paradigm, but under an age of aggression led by states using unilateral force.’

A key indicator has been the absence of broad international support for the US-Israeli campaign, reflecting concerns in countries typically allied to the US over the conflict’s legality. Europe has largely ignored President Trump’s appeals for military assistance in the Middle East, for example.

Thus, the conflict represents more than a regional war or a dispute over Iran’s nuclear programme, missiles and proxies. It signals a wider collapse of restraint in international affairs.

Bhala argues that the cumulative effect of President Trump’s tariffs, punitive sanctions and attack on Iran has been to weaken trust in US leadership and further erode America’s moral authority. ‘It’s now mainstream thinking that the US has marginalised itself in global economic and political relations because of its disruptive trade and national security policies,’ he says.

If powerful nations such as the US and Russia increasingly ignore international legal restraints, the postwar order may collapse entirely, says Federica D’Alessandra, Co-Chair of the IBA Rule of Law Forum. Writing for the Carnegie Endowment for International Peace, where she’s a non-resident scholar with the Global Order and Institutions Program in Washington, DC, D’Alessandra says that even if Iran poses a genuine threat, normalising the unilateral use of force risks accelerating global instability and, potentially, great-power conflict. ‘Any introspection that might follow in the wake of this war should focus on strengthening international law and its associated standards,’ she says.

‘It is equally imperative to reflect on the consequences that any large-scale military operations will inevitably have, and the potential costs and always uncertain outcomes that the pursuit of policy and strategic objectives through military means generally present,’ D’Alessandra says. ‘Any such considerations are, of course, aggravated if military force is used without a clear strategy, without proper authority, and without legal justification. The Trump administration has evidently given little thought to this, thus far.’

William Roberts is a US-based freelance journalist and can be contacted at wroberts3@me.com