After three weeks of effective war, the hostilities have caused severe regional spillovers, thousands of deaths, displacements of millions and a massive global energy crisis that continues to expand. If the implications are global, what’s the status of the US/Israeli strikes from the standpoint of international law?

The modern legal order is based on United Nations Charter (1945), Geneva Conventions, Rome Statute (1998) and Customary law from the Nuremberg Trials. The key rules include the prohibition of aggressive war, protection of civilians, individual criminal responsibility for war crimes, crimes against humanity and genocide. Force is allowed only in the case of self-defense and UN Security Council authorization.

The US/Israeli strikes have already violated most of these rules.    

War of aggression

Article 2(4) of the UN Charter prohibits UN member states from threatening or using force against the territorial integrity or political independence of any state. It was violated on February 28, when US/Israel launched their joint strikes against Iran.

Typically, the war was launched precisely when and because the peace talks in Oman were advancing toward a successful conclusion.

In the absence of strategic objectives and exit strategy, the U.S. has framed the actions as a campaign to dismantle “the Iranian regime’s security apparatus.” 

These efforts go back to the US/Israel 12-Day War against Iran in July 2025, when Masoud Pezeshkian, the new reform-minded Iran president, sought talks to end the conflict with the US and Israel. That was not in line with the “new Middle East” envisioned by PM Netanyahu and his Messianic far-right cabinet.

The UN Charter’s prohibition against force is not absolute, with key exceptions being self-defense (Article 51) and actions approved by the Security Council.

Yet, no such threat existed prior to the US/Israel strikes. And on March 17, 2026, Joe Kent, the Director of the US National Counterterrorism Center, resigned from his position in protest of the ongoing U.S.-led war in Iran. Kent said in no uncertain terms that “Iran posed no imminent threat to our nation.” 

This is an illegal war of aggression, instigated by leaders who have been, like Prime Minister Netanyahu, (or should be) charged for war crimes and crimes against humanity.

Preemptive war doctrine

To legitimize the unjustifiable, Washington has resorted to preemptive justifications. In this regard, the US/Israel war against Iran is just the latest link in the 25-year-long effort to sanctify power politics with preventive wars.

Since the Bush Jr. 2002 security doctrine, US administrations have stressed preemption as a central strategic instrument. While Democratic leaders (Obama, Biden) have been more moderate in rhetoric, they have coopted the same ideas.

Relying on force to prevent future threats, preventive war doctrines are often cited as violating international law because they bypass the strict legal requirements for the use of force established in the UN Charter.

Unilateral preventive war is a threat to the principle of state sovereignty, as it allows one nation to judge the “intentions” of another, without objective proof of an upcoming attack. Setting a dangerous precedent, it incentivizes other nations to use similar pretexts for their “preventive” attacks, potentially leading to global instability.

International law allows for preemptive strikes in cases of “imminent” danger. But US strategy improperly expands this to include preventive wars against threats that are not yet fully formed or do not exist – as in the cases of the 2003 Iraq War and the 2025 and 2026 Iran Wars.

Targeted assassinations

The targeted assassination of Iranian leaders is a serious violation of international law, especially when conducted outside of an active, declared war zone. Targeted killings violate the prohibition on the use of force against another state’s territorial integrity and political independence.

Outside of active hostilities, international human rights law (IHRL) applies. Under IHRL, arbitrary deprivation of life is prohibited. Targeted killings are extrajudicial killings for which the acting state is responsible.

In the context of conflict, targeted killings can violate International Humanitarian Law (IHL) principles, including distinction (targeting civilians) and proportionality. Assassinations of state officials often violate the 1973 Convention on the Prevention and Punishment of Crimes Against Persons Under International Protection.

Precedents feature the killing of the famous Iranian general Qasem Soleimani, the right-hand man of the supreme leader of Iran, the late Ali Khamenei. Soleimani was assassinated in a targeted drone strike in Baghdad in January 2020, ordered by President Trump.

From the standpoint of international law, it was an unlawful attack, as was pointed out by Ben Ferencz, the US prosecutor in the Nuremberg trials and pioneer of international law. After Soleimani’s killing, the New York Times printed Ferencz’s letter denouncing the assassination, unnamed in the letter, as an “immoral action [and] a clear violation of national and international law.”

In their first joint strikes against Iran, US and Israel assassinated the 87-year-old Ali Khamenei, the supreme leader of Iran. Demonized in the West, Khamenei supported Iran’s nuclear program for civilian use. Already in the mid-1990s, he famously issuing a fatwa against the acquisition, development and use of nuclear weapons. 

The assassination of Khamenei was still another blatant violation of international law. It was also part of the Israeli strategy to eliminate moderate leaders, whose absence is then used as an excuse for replacing peaceful diplomacy with brutal obliteration campaigns.

Crimes against humanity, forced displacement

These crimes are defined in Rome Statute Article 7, as widespread or systematic attack on civilians. Allegations are typical when strikes include targeting civilian infrastructure, economic strangulation, mass displacement, and siege conditions.

A continuity argument – “what we first see in Gaza is now spreading to Iran and, due to spillovers, into the region” – exists because similar patterns can be identified via blockade, disproportionate force, and collective punishment.

The stated efforts at regime change to undermine Iran and fragment the Shi’a state suggest that the boundary between cultural genocide targeting a broad ethnic-religious group and full destabilization is a line drawn in waters.

Allegations of ethnic cleansing, relying on deliberate forced displacement are likely over time. While ethnic cleansing is not a formal treaty crime, it is recognized in jurisprudence. It rests on forced population removal, which is the net effect of the strikes against Iran and a deliberate intention in Israel’s invasion of Lebanon.

Israel’s rapidly expanding buffer zone in southern Lebanon, extending roughly 3 to 14 kilometers north of the Blue Line demarcation, is premised on demographic engineering. In Iran, the objective to fragment the state, instigate inter-ethnic polarization and regional divides is also predicated on identity politics.

At first sight, allegations of ethnic cleansing seemed to be more relevant to Gaza and the West Bank. But with shifting objectives, forced displacement is now an overwhelming reality. The US/Israel strikes have caused displacement of 3.5 million people in Iran and over 1 million in Lebanon, with up to 22,000 killed or wounded in the former and another 3,600 in the latter.

Collective punishment, economic warfare

Combined with illicit strikes, Washington’s decades-long sanctions against Iran, most of which are unilateral, and the underlying warfare is reminiscent of economic warfare premised at collective punishment.

Combinations of economic sanctions and military strikes, particularly when invalid from the standpoint of international law, raise serious issues under humanitarian law and human rights law. In Gaza and in Iran, unilateral sanctions have caused unwarranted mass suffering violating international law.

Ever since the early 1970s, when Beirut was still called the “Paris of the Middle East,” Israel’s wars against Palestinians have destabilized Lebanon’s fragile ethnic mosaic pushing the country to the edge of default. That’s the fate PM Netanyahu would like Iran to share.

In this regard, there is a clear continuity from the Gaza War, carried out by Israel with arms and financing by the US-led West, ICJ provisional measures and ICC arrest warrant debates, to the US/Israel strikes against Iran.

The common denominators feature an inflated self-defense doctrine, weak enforcement of humanitarian law, selective application of international law and ultimately the inevitable US veto in the Security Council.

The more these violations of international law are permitted, the greater will be the costs in economic terms, the more brutal the military destruction and the more lethal the human devastation.

That’s why multilateral cooperation – across all political differences – and the enforcement of international law is so desperately needed today, before it’s too late.

Dr. Dan Steinbock is an internationally recognized strategist of the multipolar world and the founder of Difference Group. He has served at the India, China and America Institute (USA), Shanghai Institutes for International Studies (China) and the EU Center (Singapore). For more, see https://www.differencegroup.net