"The United States has launched a campaign of economic pressure to deny the [Iranian] regime the funds it needs to advance its bloody agenda," Trump told the UN, charging that Tehran's leadership sows "chaos, death and destruction."
If last year, Trump was blasting North Korean leader Kim Jong Un as the rocket man, this year, his target is his Iranian counterpart, Hassan Rouhani.
"Last month, we began reimposing hard-hitting nuclear sanctions that had been lifted under the Iran deal. Additional sanctions will resume 5 November and more will follow," he said.
The US leader insists that his strategy of "maximum pressure" honed on North Korea, and which forced Pyongyang to give up its nuclear ambitions, will work too on Tehran, even though the North has taken little concrete action to dismantle its missile and nuclear programmes.
But Iran is not North Korea, comments Saeed Mahmoudi, a professor of international law at Stockholm University.
"North Korea was a threat predominantly for South Korea and its own region, whereas Iran is considered to be a threat for Israel, US’ most important ally," he told RFI.
Mahmoudi claims that the US' unshakeable loyalty to Israel explains Tehran's reluctance to engage in talks with the US. Both leaders have ruled out direct talks at the UN General Assembly, with Rouhani insisting that Trump first needs to repair the damage he's done to the existing nuclear deal.
"Iran has good reason to be doubtful about how deep President Trump is really committed to his promises to Israel and how much he will be ready to compromise in negotiations with Iran without compromising his own pledges to Israel,” reckons Mahmoudi.
Trump withdrew from the 2015 nuclear deal in May, to the dismay of European allies, Russia and China, which had invested years in negotiations to achieve a milestone agreement on keeping Iran's nuclear ambitions in check.
Trump's hawkish stance however is justified according to Yves Bonnet, author of the book The Iran nuclear deal, an international hypocrisy.
"For years, Tehran has made us believe that it wanted nuclear weapons for civil reasons not for military purposes, but it's the same thing!" he told RFI.
"Let's not forget that Iran is developing intercontinental ballistic missiles. When you develop such missiles it's hardly to transport cheese boxes. Iran has fooled the world long enough! In Tehran, researchers work in underground tunnels. Forgive me for saying this, but why would you have to go underground unless you were up to no good?"
The remaining parties to the 2015 Iran nuclear deal however are doing all they can to keep the agreement afloat. On Tuesday, they devised a legal entity to facilitate financial transactions with Iran, to allow European companies to continue trading with Tehran even as US sanctions resume in November.
“They think that in principle no country has the right to sanction other countries for something which is otherwise fully legal," explains Mahmoudi.
Limits of EU protection
"That’s why they want to find a way to help Iran and to save this agreement, both to keep Iran within the agreement, which is good for the whole region they believe, but also to show the United States that these countries are not fully helpless and they react to the extent they can.”
However, this back-door option faces numerous challenges reckons Scott Lucas, a professor of American studies at Birmingham University.
"The EU can declare a shared payment mechanism to try to get around US sanctions, but immediately the EU cannot protect its largest companies from American sanctions if those companies continue to do business with Tehran," he told RFI.
Washington is putting pressure on governments and companies around the world to fall in line and cut their purchases of crude oil from Iran.
French companies, such as automobile manufacturer PSA, aircraft manufacturer Airbus, and oil giant Total, already have, together with other German and Dutch companies and the world's largest shipping company Mersk.
"They're all having to suspend or draw down business with Iran because the EU cannot shield them from billions of dollars in fines," says Lucas.
And this is going to get worse come 5 November when the US formally declares that any company doing business with Iran’s energy or financial sectors will face sanctions.
Yet the real pinch will be felt in Iran, where rising prices and a shrinking economy have already triggered mass protests these past few months.
US national security adviser John Bolton has vowed to impose "maximum pressure" on Tehran, while insisting that Washington is not pushing for regime change.
"John Bolton can go around saying he doesn’t want regime change, but I can go around saying all of a sudden I love Donald Trump and I would be blowing smoke," comments Lucas, adding that Bolton has long been an advocate of war with Iran.
The national security advisor and US Secretary of State Mike Pompeo are expected to headline a hawkish anti-Iran event hosted by United Against Nuclear Iran later on Tuesday.
That move may be flawed reckons Lucas, for whom the Iran nuclear deal, despite its drawbacks, is the best way of limiting Iran's uranium enrichment.
"They [the US] ripped it up because they don’t want Iran in the system unless it gives up all nuclear capacity, its ambitions in the Middle East. But the US' goal is not simply to change Iran's behavior, it wants to remove the existing regime altogether," he said.