Former US president Barack Obama made a rare public criticism of his successor Tuesday, describing Donald Trump’s decision to abandon the Iran nuclear deal as “misguided” and a “serious mistake”.

“The reality is clear. The JCPOA is working,” Obama said in a statement, referring to the deal his administration brokered in 2015. “That is a view shared by our European allies, independent experts, and the current US secretary of defense.”

“That is why today’s announcement is so misguided,” he added. “I believe that the decision to put the JCPOA at risk without any Iranian violation of the deal is a serious mistake.”

CNN reports that Donald Trump’s exit from the Iran nuclear deal was one of the most significant moments of his presidency — and cemented a sharp turn in decades of US foreign policy orthodoxy.

It also opened a new window into Trump’s political soul, showing his willingness to unleash the kind of chaos abroad he has fomented at home.

The decision added context to his “America First” foreign policy doctrine and showed he is adamant about following through on campaign promises that horrified America’s allies.

And it revealed two other pillars of the Trump presidency — a propensity to turn even the most crucial moments into a global televised drama, and his ravenous desire to eradicate President Barack Obama from the history books.

The most frequently heard criticism of Trump’s decision was that he was pulling out of the deal without offering a plan for what will happen next.

“No one has any clue on the day after. There is no strategy,” a senior European diplomat told CNN’s Michelle Kosinski, describing the State Department as “a shambles.”

But if anyone is shocked, they have missed Trump rolling the dice over the last 16 months.

The President fires people before he finds replacements, makes up policy on the fly, decided to meet North Korean leader Kim Jong Un seemingly on a whim, and slashed away at Obamacare without offering a replacement.

His legal gambits seem to come off the top of his head — with or without Rudy Giuliani.

He follows his gut, doesn’t sweat the details and thinks he’s his own best adviser. He breaks things and sees where the pieces land.

His response when asked how dangerous global crises will end is “we’ll see” — an attitude that reflects his unpredictable nature and often misplaced confidence he can control careening events.

So what Trump did Tuesday should have come as no surprise. Pulling out of an Iranian nuclear deal without knowing how Tehran or America’s allies will react or if global tensions will spike or if oil prices will surge is consistent with who Trump is.