Can Tehran regard Trump as a trusted broker of peace when he floated the idea of regime change in Iran?

These days, peace is a post on social media.

On Donald Trump's Truth Social site, it came in two parts. Part one read: "CONGRATULATIONS WORLD, IT'S TIME FOR PEACE." The Magna Carta it wasn't, but it was a peace treaty for our times - a US president announcing there would be no retaliation against Iran's missile attack.

An anxious world watching for US bombers returning to Iranian skies could cool its jets - and the primetime president could feel vindicated, having enjoyed strategic success. Trump has tweaked the politics and military landscape around Iran to suit US interests, without a single American life lost.

He had framed US intervention in Iran as an effort to prevent a "forever" foreign war, not to provoke it, and he is sitting pretty, following ugly predictions he'd be sucked into conflict. Live updates: Three killed as Iranian missiles strike Israel Then, on Truth Social, there was peace "part two".

A couple of hours after announcing non-retaliation, Trump wrote the sequel: "Ceasefire." He posted: "CONGRATULATIONS TO EVERYONE!" - saying a "complete and total" ceasefire had been fully agreed between Israel and Iran. Quite the day of problem-solving for the self-styled "peacemaker-in-chief".

Quite the day of problems unsolved too - time will tell. As deadlines loomed, neither Israel nor Iran appeared fully committed to the Trump script, and fresh missiles were fired overnight.

Daytime will test the durability of a ceasefire. There are motivations on both sides to continue a conflict in which both see the other as an existential threat.

Can Tehran regard Donald Trump as a trusted broker of peace when he floated the idea of regime change in Iran, as pursued by Israel? Can Israel be convinced to pull back on its military advantage when its instinct will be to reinforce superiority and undermine an Iranian rebuild? Trump's influence will be tested, as ever, when he flies to a NATO summit in The Netherlands today. For him, it can be a difficult crowd and one for whom he remains a mystery.

A positive result in the Middle East will help to confound their curiosity, for the better. It's the most important day for Donald Trump since the last one..