Jeremy Bowen, International Editor
It is only the third day of a new war between the United States, Israel and Iran.
It has already become a regional war, following Iran's decision to attack Arab states that are US allies, as well as its neighbors across the Gulf.
Great Britain has given up its refusal to allow America to use its bases.
The war is still escalating, and notifications about new news are just flooding my phone.
I just read a press release from US Central Command saying that three US F-15E Strike Eagles were shot down by Kuwaiti air defenses in alleged “friendly fire”.
By the time I finish this article, more rockets will have been fired and it is more than likely that some people who are now alive will be dead.
It is still too early to have any clear idea of when or how this war will end.
Once wars start, they are difficult to control.
But here are some ways the warring parties would like it to end.
Trump's definition of victory
President Trump, as always, has radiated faith in American power since he announced the war had begun in a video message recorded at his Mar-a-Lago residence in Florida.
Other presidents might have chosen a dignified address at the Resolution Table in the Oval Office.
Trump wore a shirt with the top button unbuttoned and a white baseball cap pulled low over his eyes.
He went through a lengthy indictment, claiming that Iran has posed an imminent threat to the US since the 1979 Islamic Revolution.
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Trump can always change his mind, but in that speech, he laid out the definition of his concept of victory.
It boils down to a list of things to do:
"We will destroy their missiles and raze their missile industry to the ground. It will be, again, completely wiped out. We will eradicate their navy."
"We will ensure that terrorist proxies from the region can no longer destabilize the region or the world, or attack our forces, and that they can no longer use improvised explosive devices (IEDs), or roadside bombs, as they are sometimes called, to severely injure or kill thousands and thousands of people, many of them Americans."
Trump has claimed that Iran is building missiles that can reach the United States, a claim that is not supported by US intelligence assessments.
He also claimed that Iran was close to building nuclear weapons, contradicting his own statement last summer that America had “wiped out” Iran’s nuclear facilities.
Trump believes that the US, together with Israel, can severely cripple the regime in Tehran.
If he does not capitulate, the president believes he will be so shaken that the Iranian people will have the best opportunity in generations to take to the streets and seize power.
"When we're done, take your power. It will be served to you on a platter to take. It will probably be your only chance for generations."
"You have been asking for American help for many years, but you have never received it. No president has been willing to do what I am willing to do tonight."
"Now you have a president who gives you what you want. Let's see how you use it."
Shifting responsibility for regime change to the Iranian people, even when directly calling on them to act, gives them a potential escape route later if the regime does survive.
But it can also be seen as a moral responsibility for the US to see things through, although it is an open question how much that will convince the president, who believes that an agreement can always be reached.
There is no precedent for regime change or winning a war against a well-armed enemy with the help of air power alone.
The US and its allies, including Great Britain, sent massive ground forces into Iraq in 2003 to remove Saddam Hussein.
In 2011, Libyan Colonel Muammar al-Gaddafi was overthrown by rebel forces armed by NATO and Gulf countries, and supported by airstrikes.
Trump hopes that the Iranian people can do the job themselves.
Trump's plan is a huge gamble.
All odds are against mere bombing succeeding in overthrowing the regime.
Could there be an internal pro-Western coup d'état?
It's not impossible, but it's extremely unlikely after only the third day of the war.
It is much more likely that the people who now run the regime will entrench themselves, firing more rockets, motivated by ideology and the belief that they can endure more pain than America, Israel, or the Gulf Arab states.
The most pain will be felt by the suffering Iranian people.
But he doesn't ask any questions about it.
Netanyahu's calculation
Like Donald Trump, Benjamin Netanyahu has also made statements encouraging the Iranians to take matters into their own hands.
But if they cannot overcome the regime's ruthless security forces, Netanyahu's priority is to dismantle Iran's military might and its ability to build militias across the region that could threaten Israel.
For decades, Benjamin Netanyahu has seen Iran as Israel's most dangerous enemy.
He believes that the rulers of the Islamic Republic want to build nuclear weapons to destroy the Jewish state.
On Sunday, the second day of the war, he stood on a rooftop in Tel Aviv, perhaps the very Ministry of Defense building in the heart of the city, and stated exactly how he sees the end of the war.
He said that together, Israel and America would be able to "do what I have hoped to achieve for 40 years - completely destroy the regime of terror."
He said that was a promise that he would make sure came true.
Wars always have a domestic political dimension.
Like Trump, Netanyahu faces elections later this year.
Unlike Trump, his job is truly hanging in the balance.
Many Israelis blame Netanyahu for the security lapses that allowed Hamas to attack them on October 7, 2023.
He will take a giant step towards electoral forgiveness if he can say that he led Israel to a convincing victory over Iran.
Maybe he could even be invincible.
Victory through survival
The assassination of the supreme leader and his top military advisors was a hammer blow to the Iranian regime.
But that doesn't necessarily mean it will collapse.
Ayatollah Ruhollah Khomeini and his fellow founders nearly 50 years ago designed institutions to survive wars and assassinations.
It's not a play with just one main actor.
The Syrian and Libyan states under Assad and Gaddafi were built around ruling families.
When those families were removed - Gaddafi was killed and Bashar al-Assad fled - the regimes fell.
The Iranian regime is a state system, which relies on a complex and dense network of political and religious institutions with overlapping responsibilities.
They are designed to survive wars and assassinations.
That doesn't mean they will.
The Islamic Republic is facing its greatest challenge yet.
But she had been preparing for this moment.
The definition of victory for the regime is its survival.
To achieve this, he surrounded himself with a convincing degree of protection.
It has a powerful and ruthless apparatus of security, repression, and extortion.
In January, his men took to the streets, obeying orders to kill thousands of protesters.
So far - and as I repeat, it is only the third day of the war as I write this - there are no signs that the regime's armed forces are disintegrating, as was the case with Assad's forces after he fled to Moscow in December 2024.
In addition to conventional armed forces and a well-armed police force, there is also the Islamic Revolutionary Guard Corps, with an explicit mandate to protect the regime at home and abroad.
It exists to be the force behind the velayat-e faqih, the guardian of the jurists.
This is a key doctrine of the Islamic Revolution in Iran, which justifies the rule of Shiite religious leaders.
The IRGC is believed to have 190.000 active duty members and as many as 600.000 reservists.
In addition to religious doctrine, it also guides much of the economy.
Its leaders have financial as well as ideological reasons to remain loyal.
The IRGC enjoys the support of the Basij, a volunteer paramilitary force.
Its estimated 450.000 members have a reputation for regime loyalty and violence.
I saw them in action in Tehran as the regime's first line of defense during the protests that followed the disputed 2009 elections, threatening protesters and beating them in the streets with clubs and rubber truncheons.
Behind them stood heavily armed police and IRGC members.
The Basij also had flying squads on motorcycles that raced around the city and dealt with outbreaks of rebellion.
Donald Trump has threatened the IRGC and Basij with certain death - saying "it won't be pretty" - unless they lay down their arms.
It is unlikely that his threats will change many opinions among the regime's armed men.
The Islamic Republic and Shiite Islam are imbued with the idea of martyrdom.
After hours of official claims on Sunday that the supreme leader was alive and well, a tearful television presenter on state television announced Khamenei's death, saying he had taken a sweet, pure sip of martyrdom.
Some serious Iran analysts suspect that the ayatollah held a meeting at his compound in Tehran with senior advisers at a time when much of the rest of the world believed an attack was imminent simply because he wanted to appear martyred.
The regime has a base of civilian loyalists.
Thousands took to the streets of Tehran after the death of the supreme leader, the first of 40 days of mourning.
They gathered in public squares, lighting candles and mobile phone lights, despite columns of smoke rising from the sites of US and Israeli airstrikes.
Bad precedents
The Americans believe that this time their raw power - along with Israel's - will be able to impose regime change on the enemy without creating a catastrophe.
The precedents are not good.
The removal of Iraqi leader Saddam Hussein in 2003 led to disaster – long years of war that spawned jihadist extremist movements that still exist.
Libya, a country with enough oil to provide its small population with Western living standards, is a devastated and impoverished, dysfunctional state 15 years after Gaddafi was ousted from power and killed.
The Western countries that celebrated its downfall and practically brought it about washed their hands of responsibility after the country fell apart.
Iran is a large country, almost three times the size of Iraq, with a multiethnic population of more than 90 million people.
If the regime in Iran does not fall, the worst-case scenario is that the confusion, chaos, and bloodshed that could ensue will rival the civil wars that have killed hundreds of thousands of people in Syria and Iraq.
The military action of America and Israel is crippling the Iranian military machinery.
That changes the equation in the Middle East, even if the regime survives.
Many, probably most Iranians, will rejoice if he falls.
But it will be a huge challenge to replace a regime removed by force with a peaceful, coherent alternative.
Trump's gamble is that it will still be possible and that this war will transform the Middle East into a better and safer place.
The obstacles to this pose major challenges.
Images at the beginning: AFP via Getty Images
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