THE HAGUE, Netherlands (AP) — As U.S. and Israeli forces pounded Iran, and Tehran and its affiliates retaliated by firing missiles at targets across the Mideast on Monday, the international legal order was caught in the crossfire.
At the heart of the post-World War II global order — United Nations headquarters in New York — Secretary-General António Guterres told the Security Council on Saturday that U.S. and Israeli airstrikes violated international law, including the U.N. Charter. He also condemned Iran’s retaliatory attacks for violating the sovereignty and territorial integrity of nations in the Mideast.
Officials in the Trump administration insist that the military campaign is a lawful measure to ensure Tehran does not build nuclear weapons. "It’s a matter of global security. And to that end, the United States is taking lawful actions,” Trump's U.N. ambassador, Mike Waltz, said.
Iranian Foreign Minister Abbas Araghchi wrote in a letter to the U.N. on Sunday that the killing of Supreme Leader Ayatollah Ali Khamenei “constitutes a grave and unprecedented breach of the most fundamental norms governing relations among States.”
On Monday, Defense Secretary Pete Hegseth bullishly defended the U.S. military campaign. "No stupid rules of engagement, no nation building quagmire, no democracy building exercise, no politically correct wars. We fight to win and we don’t waste time or lives,” he said at the Pentagon.
The war with Iran comes less than two months after U.S. forces swooped into Caracas to capture former Venezuelan President Nicolás Maduro and fly him to New York to face justice.
David Crane, an American expert on international law and founding prosecutor of a United Nations court that prosecuted crimes in Sierra Leone, wrote in an analysis that U.S. attacks in Iran and Venezuela “highlight a dangerous trend: the normalization of unilateral force as a tool of foreign policy. Even when the outcome is positive, the violation of international law and constitutional limits sets a precedent that threatens global stability and undermines America’s own legal foundations.”
In Washington, many Democrats have called the strikes illegal. They argue that under the Constitution, only Congress has the power to declare war. They say the Trump administration failed to lay out its rationale or plan for the military strikes, and the aftermath.
Congress hurriedly scheduled a war powers debate for Monday over Trump’s authority to bomb Iran.
Under an amendment to the founding treaty of the International Criminal Court, aggression is described as “the use of armed force by a State against the sovereignty, territorial integrity or political independence of another State, or in any other manner inconsistent with the Charter of the United Nations.”
Among acts of aggression listed by the court are: “Bombardment by the armed forces of a State against the territory of another State or the use of any weapons by a State against the territory of another State.”
Neither the United States, Israel nor Iran are members of the court, meaning the court does not have jurisdiction in the ongoing war unless it is referred to ICC prosecutors by a Security Council resolution.
Under the U.N. Charter, nations are only permitted to use force against another nation if it has been authorized by the Security Council or in self-defense, said Marieke de Hoon, an associate professor of international criminal law at the University of Amsterdam.
De Hoon said the attacks on Iran amount to a crime of aggression.
“It is a violation of the prohibition to use force, the cornerstone of the international legal order, and there is no legal justification for it: it is not a self-defense against an armed attack by Iran or an imminent threat” of an attack, "nor is there a UNSC resolution to authorize use of force,” she told The Associated Press. “Regime change moreover violates the sovereignty of another state.”
Iranian authorities have a history of brutal repression of dissent and sponsoring extremism that has destabilized the Mideast. The country's nuclear ambitions were targeted by Trump last year in military strikes on sites in Iran.
But De Hoon said that is not enough to justify the U.S. and Israeli bombardments.
She said that under international law Tehran has the right to self-defense, but she added that "Iran is not allowed to attack civilian infrastructure in other countries. Its response needs to be proportionate to stop the aggression, without offering itself a legitimation toward, for instance, regime change in the aggressor country.”
Crane said that while the removal from power of Maduro and Khamenei could potentially boost regional stability and reduce suffering and ultimately improve the prospects for peace and democracy, “international law does not permit states to unilaterally decide which tyrants to remove by force.”
Marko Milanovic, a professor of international law at Reading University, said that in peacetime, “it is a clear violation of international law to assassinate the head of state or government of some other state.”
He said heads of state and government “enjoy personal immunities and inviolability, and any attacks against them would also violate the sovereignty of their state.”
That changes in wartime, he added, saying that if political leaders also are members of the armed forces, “then they are combatants like any other members of the armed forces and are not immune from attack.”
Associated Press writer Jovana Gec in Belgrade, Serbia, contributed to this report.
This story has been corrected to show Marieke De Hoon's title as associated professor.
President Donald Trump waves after arriving on Marine One on the South Lawn of White House, Sunday, March 1, 2026, in Washington. (AP Photo/JMark Schiefelbein)
A plume of smoke rises after a strike in Tehran, Iran, Monday, March 2, 2026. (AP Photo/Vahid Salemi)
Plumes of smoke from two simultaneous strikes rise over Tehran, Iran, Monday, March 2, 2026. (AP Photo/Mohsen Ganji)
