Public reassurance is one of the first duties of the government in difficult times. The early months of the Covid pandemic offer a case study in how to get this wrong. Boris Johnson was paralysed by indecision and denial of the severity of what was unfolding. Panic-buying cleared supermarket shelves of essential goods.

Sir Keir Starmer is unlike Mr Johnson in temperament and work ethic, but he too is struggling to get ahead of events in a global crisis. It isn’t easy when the origin of turbulence is a superpower gone rogue. Donald Trump’s impulsive actions can’t be anticipated with epidemiological precision like a virus.

Sir Keir has extremely limited influence over the course of events in the Middle East. He showed sound judgment in refusing to put British forces at Mr Trump’s disposal to bomb Iran. It is not Britain’s war, as the prime minister says, but it is Britain’s problem and will be for some time to come.

Even in best-case scenarios, where the strait of Hormuz is promptly reopened and stays unobstructed, the Gulf states’ capacity to export energy will take years to recover. Vital commodities will not come straight back on stream. Shortages are likely; a period of higher inflation is certain.

It is hardly surprising that Rachel Reeves declares herself “frustrated and angry” by the US decision to start a war with vague objectives and no exit strategy. The chancellor’s plans, including £24bn of “fiscal headroom” projected in March’s spring statement, have been overtaken by events. She will come under growing pressure to provide emergency support for households facing higher bills. International conflict provokes demands to increase defence spending, while slower growth depletes Treasury revenue, and borrowing costs remain high. Painful tax and spending choices loom on the horizon at a time when public reserves of goodwill towards the government are depleted.

The prime minister’s preferred method for dealing with such trials is to carry on as normal, insisting that he understands public discontent, sympathises and is getting on with the job of delivering improvements to people’s lives, which will be felt in due course. There is no evidence that this message, lacking a compelling sense of overarching purpose and governing vision, resonates with voters.

The scale of what could be coming in the weeks or months ahead demands a different approach. Britain might be spared the energy privations already afflicting some parts of Asia, but it would be unwise to bet on a mild price shock, resilient supply or a shallow dip in global output. The public needs to be prepared for the possibility of significant disruption and encouraged to use energy more efficiently.

Ministers understandably don’t want to trigger panic by raising the spectre of shortages; nor is it helpful for the economy to depress consumers by promising bad times ahead. But it would also be irresponsible to pretend that nothing has changed or that existing budgets are sufficient to carry everyone through another spike in living costs.

There is a path between avoiding needless anxiety and indulging denial. It requires sober assessment of risks and conspicuous readiness to mitigate them. Sir Keir cannot be blamed for the economic consequences of a war he didn’t start, but he should have a plan by now – and be seen to have a plan for a severe and prolonged crisis.

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