Barely a week after American bombs rained down across Iran, Donald Trump picked up the phone to a reporter at the New York Post.

“I have a plan for everything, OK?” the president snapped, after being asked about turmoil in the energy markets. “You’ll be very happy.”

At the time, Iran’s regime was reeling from the assassination of Ayatollah Ali Khamenei in a joint US-Israeli operation on 28 February. Oil prices surged as Tehran moved to blockade the Strait of Hormuz, through which a fifth of the world’s oil passes each day.

Six months on, Trump is caught in a quagmire of his own making. Both sides continue to trade strikes, shipping through Hormuz has slowed to a trickle and the war is no closer to a resolution. Oil prices are still 25 per cent higher than in February and the US military continues to record casualties, while Trump’s approval rating has fallen to its lowest level since he took office.

Despite his claim to have destroyed Iran’s military, analysts say it is damaged but remains intact. Meanwhile, control of Hormuz has given Tehran a vital piece of leverage, with consumers across the world facing hikes in energy prices.

The Independent has examined data that lays bare the astonishing cost of Trump’s war to the global economy, the wider Middle East, the US military and his own domestic popularity. Without a face-saving exit strategy, experts say, the US is at risk of “drifting towards a form of forever war” that could prove to be Trump’s greatest miscalculation.

The bitter human cost of the war

More than 8,000 people across the Middle East have been killed since 28 February, according to an aggregate of local tallies. While both sides have scaled back strikes in recent months, casualty figures continue to grow.

According to the Iranian government, at least 3,468 Iranians had been killed by mid-April. The US-based Human Rights Activists News Agency put the figure at 3,636, including 1,701 civilians, in May.

As of this week, the Pentagon has tallied 14 US service member deaths and 417 injuries directly linked directly to its Operation Epic Fury. A further four have been killed in overseas operations since 7 July, while 341 have been injured, for a total of 18 deaths and 758 wounded. Another 60 injuries were listed just last week.

Civilians have been caught up in the conflict. The US military was accused of killing a young family with a 907kg bomb in renewed strikes on Iran’s Qeshm Island at the end of July. An interim agreement to stop the fighting, signed in June, was repeatedly flouted by both sides before being scrapped entirely.

An Indian sailor was killed and eight others were injured when two oil tankers were struck by cruise missiles in the strait last month. And three sailors were reported to have been killed in US strikes in June. There have been more than 150 deaths recorded across the wider region linked to the conflict.

The spiralling economic cost

Iran’s grip of the Strait of Hormuz has sent ripples through the global economy by halting shipping and forcing up the cost of oil. Benchmark crude prices are still around $90 per barrel, up 25 per cent from $72 on the eve of the conflict. In the US, gasoline prices have risen by around 30 per cent over the past year.

Energy inflation has cost consumers $91.6bn as of 26 August, according to the Watson School of International and Public Affairs. They say the higher cost of gasoline has cost the average US household an additional $381.64 since the start of the war. The Center for American Progress estimates that, as of 20 August, the war has cost the average US household $1,200 in total.

The cost has also been felt in the UK, despite efforts to stay out of the conflict. The National Institute of Economic and Social Research assessed this month that the energy shock would take 0.3 per cent of GDP off the economy this year and 0.2 per cent the next. Real GDP will be £12.8bn lower than it was forecast to be prior to the war – equivalent to the budget of the Ministry of Justice.

British households are now bracing for higher bills after Ofgem raised the domestic energy price cap by four per cent this week and inflation hit 2.9 per cent. The Resolution Foundation think tank assessed in April that higher energy prices alone would leave the average British household £480 worse off this year than had the war not happened.

The damning political cost ahead of the US midterms

Trump’s popularity has sunk to a new low among voters as the war takes its toll. Just 33 per cent of Americans said they approved of the president’s performance in the White House so far, according to a Reuters/Ipsos poll that concluded on Monday.

The survey found just 31 per cent of ​Americans support US military action against Iran, down from 37 per cent in March and driven by a fall in support from Republicans. Even some of Trump’s allies have jumped ship; the former US representative Marjorie Taylor Greene said last week the Republicans “could get smoked” in the November midterms, in part over broken trust around a promise of “no more foreign wars”.

Trump will be under pressure to show progress towards resolving the crisis and bringing down energy prices in the lead-up to the midterms, in which all seats in the House of Representatives will be contested, along with a third of the Senate. Following the 18 August primaries, polling showed the Democrats with a six-point lead.

Dr Lindsay Newman, associate fellow with Chatham House, told The Independent that Trump had taken lessons from the quick ousting of Venezuela’s Nicolas Maduro in January and misjudged a conflict with Iran.

“Iran was always going to be a much bigger and more complex proposition … Operation Epic Fury represents tactical success but strategic failing,” she said.

“Trump wanted a quick operation and instead got a Middle East-sized headache … The US administration finds itself six months along no closer to a conflict resolution, even after toggling between tactics.

She added: “As Trump has gone searching for an offramp, the US strategy now is an economic security play to squeeze Iran. This new approach makes sense. It has been clear for months that Trump was not willing to pay the cost to end the war militarily, and there was little domestic appetite to do so.”

Andreas Krieg, associate professor in security studies at King’s College London, told The Independent: “Trump does have a way out, but it requires redefining victory. He needs a deal that allows him to say the United States restored freedom of navigation, forced Iran to accept restrictions on its behaviour and imposed unprecedented economic costs.”

The cost to US influence in the region

The war has left the Middle East in turmoil, damaging US relationships with Gulf states and degrading American diplomatic power in the region. The war was meant to remove Iran as a threat to the Middle East, but analysts say it has instead emboldened Tehran.

Iranian missile and drone attacks have hit previously safe Gulf Arab states and disrupted air travel, while attacks on shipping have raised insurance and transport costs across the region. Iran is now negotiating for a deal with Oman to control passage through Hormuz, which before the war was an international waterway and free to transit.

The US has meanwhile threatened its old ally Oman, all while depleting its stockpiles and reducing readiness for a potential future confrontation.

Dr Krieg assessed that the biggest loss for the US is the strategic freedom of manoeuvre as it absorbs military assets, intelligence and political attention “at precisely the moment Washington wants to concentrate resources on Asia”.

”The US has won most of the battles, but it it cannot win the war,” he said.

Dr Newman said: “The conflict in Iran has truly been an application of the Trump Doctrine to use all available means at any time to champion core American interests as defined by the US administration. It is an approach of heavy footsteps and pulling many levers. Six months in, the report card is very mixed.”