A central question for the global economy came into stark relief this week ahead of President Trump’s address to the nation about the war in Iran: Would he be willing to leave without reopening the Strait of Hormuz?

Trump essentially laid out that scenario as his possible approach on Tuesday, telling reporters he expected to end the war after two to three additional weeks.

At that point, he said, “What happens in the strait, we're not going to have anything to do with,” and other nations may need to “fend for themselves.”

The president has falsely claimed for weeks that the US has no interest in what passes through the critical shipping channel.

He followed up Wednesday morning with another wrinkle, claiming that Iran is asking for a ceasefire but that he will consider it only when the strait “is open, free, and clear.”

Trump is scheduled to deliver an address to the nation at 9 p.m. ET from the White House that his press secretary described as “an important update on Iran.”

The problem for the White House is that global energy markets would undoubtedly be even further unsettled by any scenario where Iran is able to indefinitely control traffic (and even charge fees) in the 21-mile-wide waterway through which about one-fifth of the world’s oil passes.

On Yahoo Finance Tuesday morning, Bianco Research president Jim Bianco called the economic effects of that scenario “incalculable.”

“Basically, you would be elevating Iran to a superpower … only their oil would get out, and they would probably try and use it to crush the West,” Bianco said.

It’s all evidence of the conundrum facing the White House, torn between those dire economic projections and an equally strong desire to wrap up US engagement.

The issue is expected to be center stage in Trump’s speech tonight.

Trump is promising to end the war but is also considering escalation — perhaps to target Iran’s nuclear sites or its energy infrastructure or to open the strait — with US ground forces now in the region.

Some close market watchers in recent days have expressed skepticism that Trump — no matter what he says publicly — would really be willing to walk away from the strait given fears that energy prices could then shoot even higher if he does.

Signum Global Advisors, in a note to clients on Tuesday morning, said it was “extremely unlikely” that Trump would end the war without first at least trying to reopen the strait.

The group offered three reasons: damage to the US economy, adverse impacts on Trump’s Persian Gulf allies, and how leaving the strait in Iranian control “would put the US at a comparative global disadvantage.”

Read more: How oil price shocks ripple through your wallet, from gas to groceries

Tobin Marcus of Wolfe Research wrote in his own note Tuesday that he thinks the president “might be willing to withdraw without militarily reopening the Strait eventually if the cost of the war becomes intolerable, not that he's planning to do so imminently, “ given the immediate economic pain that would likely follow such a move.

Indeed, a flurry of economic observers have warned that the effects on the global economy could be dramatic if shipping isn’t open at the end of the conflict.

Read more: How oil price shocks ripple through your wallet, from gas to groceries

BlackRock CEO Larry Fink said last week during an interview with the BBC that oil prices could reach $150 per ​barrel and cause a global recession if Iran remains “a threat ​to the Strait of Hormuz” after the end of hostilities.

Patrick De Haan, GasBuddy’s head of petroleum analysis, added on X Tuesday that “ending a war while leaving Hormuz closed isn’t ‘peace’, it’s surrendering the world’s most critical oil chokepoint, guaranteeing higher energy prices, economic shock, and long-term instability.”

Another factor fueling uncertainty is that Trump’s public pronouncements often veer wildly.

On Monday, he issued an ultimatum to Iran, posting that “if the Hormuz Strait is not immediately ‘Open for Business,’” the US would retaliate by “obliterating” things like electricity infrastructure, Kharg Island, and even desalination plants.

But roughly 24 hours later, Trump had pivoted and declared that the strait is not his problem, telling other nations to “go get your own oil!”

That was before his additional commentary on Tuesday and Wednesday added further confusion — a pattern that has persisted since the beginning of the war.

Some days, the president uses absolutist language on the need to reopen the strait immediately. In fact, Monday’s message was at least Trump’s fifth ultimatum demanding Iran fully open the area for shipping or face violence.

But other days, he has downplayed the importance of the waterway and falsely claimed the US doesn’t rely on it, including at one point predicting the strait would “open itself.”

This story has been updated with additional developments.

Ben Werschkul is a Washington correspondent for Yahoo Finance.

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