Alarm at Trump's unsubstantiated claim that Beirut blast was an 'attack'

Donald Trump’s unsubstantiated claim that the massive explosion in Beirut was a bomb attack has revived fears of the president’s potential to foment international crises.

In off-the-cuff remarks at the White House on Tuesday, Trump called the blast a “terrible attack”.

“I’ve met with some of our great generals and they just seem to feel that this was not some kind of a manufacturing explosion type of event,” the president told reporters. “It was a bomb of some kind.”

Soon after, CNN quoted Pentagon officials as saying there was no evidence of any attack, raising the question of where Trump got his information. Lebanese officials were reported to have sought urgent clarification from US diplomats.

The defence secretary, Mark Esper, said on Wednesday: “Most believe that it was an accident as reported.” But he added that the Pentagon was still gathering information about the explosion.

In a statement about Beirut, the state department referred to the “horrible explosion” but made no mention of an attack.

The Beirut government says the explosion was caused by a warehouse full of ammonium nitrate igniting, though the initial cause of the fire is still unclear.

The White House gave no guidance on Wednesday as to whether Trump had received a top secret intelligence briefing, had seen something on Twitter – or just made up the claim and imagined a conversation with US generals.

It has become the norm for US officials to quietly correct the thicket of mistakes and lies embedded in Trump’s daily discourse, but applied to a fragile and volatile corner of the world, the stakes are higher.

“I would advise against listening to Donald Trump at the best of times, let alone the worst,” Tom Fletcher, a former British ambassador to Lebanon, said.

“You can’t show up unprepared for the Middle East. Careless messaging from the White House has consequences, even when no one takes the tweeter seriously. I hope future American presidents will try to help put out fires in the region, not fan them.”

The Democratic senator Chris Murphy said on Twitter: “Before the explosion, Lebanon was already in dire crisis, with a collapsed economy and sectarian tensions at a boiling point.

“I can’t imagine anything worse right now than Trump making unfounded claims of an ‘attack’,” Murphy added. “Could set off something truly awful in Lebanon.”

The worst nightmare looming over the Trump administration is that the president might shoot from the hip at the White House podium during a nuclear standoff.

In his documentary-style novel, The 2020 Commission Report on the North Korean Nuclear Attacks Against the United States, academic and nuclear expert Jeffrey Lewis imagines a scenario in which the US slides into a devastating conflict, propelled by the president’s impulsive tweets and remarks.

“I would feel a lot better if the real world looked less like my book,” Lewis said on Wednesday.