The US and Israel have launched extensive, coordinated attacks on numerous targets across Iran, prompting retaliatory strikes in the region. Donald Trump neither tried to obtain Congressional approval, nor did he pursue a United Nations security council resolution ahead of these actions. And the attack has come in the middle of talks between Tehran and Washington.The facts are clear. This is an illegal war, both in terms of US law and international statutes. The US president has repeatedly said that Iran can’t be allowed to develop a nuclear weapon. But the IAEA has stated that there is no evidence that Iran is pursuing a nuclear weapon. Iran’s foreign minister, Abbas Araghchi, said after the latest round of talks that “good progress” was being made on a deal to limit Iran’s nuclear programme in return for sanctions relief. Now, from everything that the US president is saying, the goalposts have shifted from a nuclear deal to an attempt to force regime change.So bombs are falling on various cities in Iran, family members are hiding, tragedies will inevitably happen and the innocent will suffer. This is the endpoint of a longstanding campaign by the US and Israeli right-wing to reshape the Middle East and the wider Muslim world at the barrel of a gun. This is yet another intervention in a long history of disastrous foreign moves that have destabilised the country since Britain and the Soviet Union deposed Reza Shah Pahlavi in 1941 and the CIA and MI6 orchestrated a coup to depose Iran’s democratically elected prime minister, Mohammad Mossadegh, in 1953.The consequences of this attack are likely to be dire for the region and the world. Already, Iran has retaliated by targeting US bases in Kuwait, Qatar, the United Arab Emirates and Bahrain and the first reports of casualties are emerging. Iran is unlikely to hold back. It’s clear that the Islamic Republic is viewing this as an existential threat. Tehran will call on its allies in the region, the Houthis in Yemen, the Popular Mobilisation Forces in Iraq and Hezbollah in Lebanon which – despite being weakened over two years of attacks by Israel aided and abetted by the United States – have the capacity to expand the conflict throughout the region. Iran has already indicated in recent drills with the Russian Navy that it may be capable of closing off the Strait of Hormuz, through which around one-quarter of the world’s oil and one-third of its liquefied natural gas travel. As a consequence, oil prices will explode and the world economy will suffer.Clash of civilisationsThere is a cultural component to this war, too. Israel and the US are conducting this war during the month of Ramadan. Muslims all over the world are fasting. For billions of them, this is the month of spirituality, peace and solidarity. Images of Iranian Muslims being killed by Israeli and US bombs threaten to further a clash of civilisations narrative which pits the Judeo-Christian world against Islam. Muslims in European capitals, together with anti-war activists, will see this war as a clear aggression on the part of the US and Israel. Global public opinion will not be easily swayed into the direction Trump and Netanyahu would like.And it must be asked, what will the leaders in Moscow and Beijing be thinking as they watch this illegal war and what might this mean for Ukraine and Taiwan? Vladimir Putin and Xi Jinping are close to the government of Iran and will condemn this war. At the same time, they must feel emboldened to pursue their own agendas with military might.So Trump and Netanyahu’s attack on Iran has the potential to plunge the world into deep crisis. Expect more refugees, more economic turmoil, more trauma, death and destruction. The only hope now is that cooler heads among world leaders can prevail to contain this conflict and to limit the actions of Trump and Netanyahu. Diplomacy has to be prioritised. Attempting to force regime change by launching an illegal war is foolhardy. If Iran is further destabilised, the entire Middle East and beyond will be plunged into utter turmoil. From there the outcome for the whole world is dangerously uncertain.Arshin Adib-Moghaddam does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.