The pair today ended two days discussions at the Trump southern White House of Mar-a-Lago, to the backdrop of increased military tension in Syria.
They were sitting down for their first dinner together Friday morning Australian time when the missile strike on a Syrian air base ordered by President Trump was launched.
The host marked the conclusion of the visit with in his usual style of repeated emphasis: "In the long time we are going to have a very, very great relationship."
But the US President ended up with little except the beginning of a personal relationship with President Xi.
In diplomatic terms it was more sweet seduction than summit, long mapped out by the Chinese who have resisted Trump provocations during the US election campaign and since he was sworn in.
Mr Trump had warned of a trade war against Beijing, and a literal war against a nuclear-armed North Korea, and he aimed no substantial policy shifts from Mr Xi.
"I just want to say that President Xi and all of his representatives have been really interesting to be with," Mr Trump said.
"I believe lots of very potentially bad problems will be going away."
President Xi said more soberly: "We have engaged in deeper understanding, and have built a trust.
"I believe we will keep developing in a stable way to form friendly relations ... For the peace and stability of the world, we will also fulfil our historical responsibility."
He congratulated Mr Trump on his "excellent preparation".
On trade there was agreement for a 100-day assessment of differences on economic issues.
Essentially it was the familiar process of creating a committee but was described by US Commerce Secretary Wilbur Ross as "a very big sea change in the pace of discussions".
Mr Ross said the Chinese had addressed ways to shrink the massive trade deficit the US has with China, the balance of which Trump had used to accuse China of stealing American jobs.
But there was no accommodation of Mr Trump's demand that China increase pressure on North Korea to drop its nuclear weapons program.
"There was no kind of a package arrangement discussed to resolve this," said Secretary of State Rex Tillerson.
There is speculation then 59 US missiles fired into Syria were a practical demonstration of the aggression a Trump administration might show in North Korea.
President Xi would not have been happy with the display of fire power during his time at the Trump resort although there was no indication of this in public.
The next big moment in US-China relations, and the sweet seduction, will be Mr Trump's visit to Beijing next year.
