It all looked so promising: smiles all round, plenty of arm-patting and tete-a-tetes.
When US President Donald Trump met his "friend", North Korean leader Kim Jong Un, for an intimate dinner on Wednesday night at the Sofitel Legend Metropole hotel, the two bonded over grilled sirloin and chocolate lava cake.
At a photo opportunity before they ate, the two men had only praise for each other and optimism about a deal to come the following day.
"Disbelief and misunderstandings were everywhere, and old hostile habits were getting in our way, but we've overcome it well, come face to face and walked all the way to Hanoi in 260 days," said Mr Kim, smiling, through an interpreter.
President Trump was no less effusive. "I think you will have a tremendous future with your country - a great leader. And I look forward to watching it happen and helping it to happen."
The positivity did not abate on the morning of their negotiations. Mr Kim even broke his silence and responded to questions from journalists just before the talks.
"If I wasn't ready for such a thing, I wouldn't be here," he said when asked if he was prepared to give up his nuclear weapons.
But barely two hours later, everything had fallen to pieces, and he had zoomed off in his Mercedes-Benz S600 Pullman Guard armoured limousine with his elite bodyguards in tow. The lunch table, laid out with fine chinaware on a crisp white tablecloth at the Metropole hotel, was left empty.
In Singapore last June, no one knew for sure if the two unpredictable arch rivals were going to shake hands on a deal or stomp out of the room, so the atmosphere in the hot 32 deg C island air was one of apprehension for days.
But Hanoi was different, with its celebratory 17 deg C cool breeze the past few days. It was as if regular Vietnamese folk had a hunch that all was going to go well, and the city would go down in history as the one where Kim Jong Un denuked and Donald Trump earned his Nobel Peace Prize.
Yet, it was not really a hunch because all the signs pointed to a deal greater than what was achieved in Singapore last June.
The Vietnamese authorities, enthusiastic about putting Hanoi front and centre of every newspaper, news website and TV news programme in the world, prettified streets with blooming flowers in a riot of colours and cleaned up every scrap of litter.
In true socialist fashion, they even lined up well-wishers bearing welcome signs, flags and flowers to greet the Trump-Kim motorcades.
As about 200 journalists were being bussed to the JW Marriott yesterday afternoon for a scheduled press conference by the US President, they got wind that something had gone horribly wrong.
The negotiations had ended abruptly with no lunch, no signing and no deal. What was slated as a triumphant news announcement at 3.50pm became a 2pm event instead, with officials hurrying journalists to take their seats and cameramen to set up their equipment.
What happened in Hanoi yesterday will be the stuff of conversation for the following days and months. The Vietnamese capital city will hopefully continue to reap the benefits of the world attention it has garnered over this one week, but there will likely be no third summit city for possibly years to come.