Across the world on Wednesday night, millions of people will tune in to watch Donald Trump deliver a primetime update on the war in Iran. Many will hope for some insight on how the war ends and what might come after.

The Trump administration has, so far, given little clue as to what prompted the hastily-arranged remarks, or whether they will mark the beginning of the end of the conflict or a potentially bloody escalation.

This ambiguity is, at least partly, by design. Trump often changes course or leaves his thinking a mystery to all but a small inner circle of supporters, which he has acknowledged leaves friend and foe alike wondering about his next move.

The president knows that the address comes at a critical time in his presidency and amid mounting domestic pressure to find a way out of the conflict.

Poll after poll has shown that Americans have little appetite for a protracted conflict in Iran, particularly if it involves the prospect of US soldiers on Iranian soil.

A Reuters poll released this week found that two-thirds of Americans believe the US should work to swiftly wrap up its involvement in the war, even if the administration's stated military objections are not fully accomplished.

Closer to home, many Americans are increasingly wary of higher prices at the petrol pump, which this week crossed the average of $4 a gallon for the first time in years.

For a president who, pre-war, often pointed to lower petrol prices as a mark of success, this trend represents a challenge.

Imran Bayoumi, a geostrategy expert, noted that the deep domestic unpopularity of the war could pose a problem ahead of midterm elections if the war were to drag on.

This leads to speculation regarding the legacy of US involvement in Iran, as the president will likely discuss the potential conclusions of the conflict amidst its shifting strategies.

His unpredictable rhetoric points toward a final phase, with promises of moving towards a ceasefire while hinting at continued military action if conditions are not met.

What Trump says tonight will be closely observed by allies and adversaries alike, as they ponder whether his declarations are a tactical maneuver or an earnest roadmap for US-Iran relations.