(CNN) With only hours remaining before a historic summit between the leaders of the United States and North Korea, it's easy to lose sight of what President Donald Trump (and some of his top staffers) said and did just before arriving in Singapore: Blow up an international gathering with some of America's closest allies with a combination of erratic behavior and hugely impolitic statements.

Whatever happens in Singapore over the next day or two, it's uniquely possible -- and maybe even likely -- that what Trump did in Quebec on Friday and Saturday will matter more in the country's long-term geopolitical future, and not in a good way.

Let's detail what happened in the 36-ish hours Trump spent in Quebec -- and what he and his allies said once he left.

Before Trump even jetted to the conference on Friday morning, he floated the possibility of Russia rejoining the G7. (Russia was kicked out of the group after invading Ukraine and annexing Crimea in 2014.)

Trump arrived late for a gathering of G7 leaders focused on gender diversity on Saturday morning. They started the meeting without him.

Trump held a, um, wide-ranging news conference before he left Quebec to jet to Singapore. In that presser, he described the meeting as a "10" out of 10 and insisted he had very close personal relationships with, among others, Canadian Prime Minister Justin Trudeau, French President Emmanuel Macron and German Chancellor Angela Merkel.

After (apparently) watching a Trudeau press conference on Air Force One, Trump took to Twitter to attack the Canadian Prime Minister. "PM Justin Trudeau of Canada acted so meek and mild during our @G7 meetings only to give a news conference after I left saying that, 'US Tariffs were kind of insulting' and he 'will not be pushed around,'" tweeted Trump. "Very dishonest & weak. Our Tariffs are in response to his of 270% on dairy!"

Chief Trump economic adviser Larry Kudlow went on CNN's "State of the Union" and called Trudeau's news conference a "betrayal," adding: "He stabbed us in the back."

Peter Navarro, a trade adviser for Trump, was even more damning in his comments about Trudeau. "There's a special place in hell for any foreign leader that engages in bad faith diplomacy with President Donald J. Trump and then tries to stab him in the back on the way out the door," Navarro said on "Fox News Sunday." "And that's what bad faith Justin Trudeau did with that stunt press conference. That's what weak, dishonest Justin Trudeau did, and that comes right from Air Force One."

REMINDER: This is Canada we're talking about.

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