President Masoud Pezeshkian came to New York with a written text. After hearing Donald Trump at the same rostrum the day before, he set it aside, telling delegates he had prepared a speech before the US president called Iran a terrorist state. He was, by most accounts, the first leader to speak at the UN in person in the middle of a war with the United States. Speaking from the heart is why the historic address will be heard well beyond the hall. It should not hide how precise it was - legally, morally and strategically. He opened with photographs of dead children, victims of American and Israeli bombs, and a direct reply: "We have been the victims of terrorism." "We have only defended ourselves. We are not terrorists." Palestinians know this inversion well. A people defends itself, and the aggressor calls the defence terrorism. Anyone who has watched the last seven months with clarity will recognise it. He answered the bullying Trump had put on display, musing aloud about annihilating Iran, by standing on the ground of law. Everything said against Iran from that podium, he argued, contradicts the UN Charter. He is right. Article 2(4) forbids not only the use of force but the threat of it, and a head of state weighing the annihilation of a fellow member state before the General Assembly is as plain a threat as the Charter's drafters could have imagined. Iran asks for no special treatment, only the sovereign equality the Charter promises every member. On the nuclear file his formula was "no nuclear weapons, and no limitations to peaceful nuclear technology." That is the NPT's own bargain: the treaty bars non-nuclear states from acquiring the bomb, and its Article IV guarantees the "inalienable right" of every party to peaceful nuclear energy "without discrimination." He was equally plain that Iran built its defences to guarantee that any strike on its cities is answered. In Nicaragua v. United States, the ICJ held that international law places no limit on a sovereign state's armaments beyond what it accepts by treaty. He also took apart the Israeli-made story that Iran's political establishment is on the verge of collapse, and that Iranians would welcome foreign invaders. For seven months people have been in the streets daily in support of the defence effort. The same fact answers Trump's claim that the Iranian state has killed tens of thousands of its own people. A population does not rally under bombardment behind a government it regards as its killer. Then he named the war crimes. He showed images of the Shajareh Tayyebeh primary school in Minab and of a sports hall in Lamerd where children had been playing. A weapon that scatters tens of thousands of tungsten fragments cannot be used on a school or a gymnasium without striking indiscriminately. A UN fact-finding mission reported this month that there are reasonable grounds to believe the United States committed war crimes in the February 28 strikes. The US delegate left the hall during this passage. Pezeshkian drew the parallel with Gaza, where the ICJ has ordered Israel to prevent acts of genocide and the International Criminal Court has issued arrest warrants for its prime minister and former defence minister. He turned next to Israel's nuclear arsenal. Israel stays outside the NPT and accepts no comprehensive safeguards, although the Security Council called on it in Resolution 487 of 1981 to place its facilities under IAEA safeguards, and the General Assembly repeats the call every year. Israel has struck the capitals of its neighbours in breach of the Charter and carries out a documented pattern of war crimes, yet keeps its weapons with impunity. Iran, which has acted only in self-defence for two centuries, is sanctioned and attacked instead, although its facilities remain under an IAEA safeguards agreement. On Hormuz, he described a strait closed to Iran even as it serves to ship missiles and weaponry into the surrounding region. The law of the sea does not allow this. The 1982 Law of the Sea Convention, which Washington invokes but has never ratified, requires ships passing through a strait to refrain from any threat or use of force against the states bordering it. Under the older rule of innocent passage, a ship serving an attack on the coastal state is no longer in innocent passage at all. Iran will not be shut out of its own waters while others use them to make war on it. He closed on the indivisibility of security: it exists for everyone in the region or for no one. The idea has a long pedigree. European states wrote it into the Helsinki Final Act in 1975 and restated it in 1999, pledging not to strengthen their own security at the expense of others. "We want strong neighbors," Pezeshkian said. Iran has always been open to diplomacy, "without accepting the language of force." @drpezeshkian