President Trudeau has been called the "anti-Trump" in a German newspaper, while at home, supporters on the left have bit their tongue as he renews neighbourly ties with the Republican, for the sake of a key trade and security relationship.
The Canadian leader has not shelved his liberal values, which he touts every time he stands in front of a microphone.
But he also hasn't denigrated Trump to advance his agenda or to score cheap political points - at least not overtly.
The result has been seemingly strong ties with the Trump administration, with no loss of political capital for Trudeau at home or abroad - rather a deft maneuver by the Canadian leader.
"It's a fascinating relationship," said Ian Capstick, a political analyst and head of Media Style in Ottawa.
"I don't know if I would call it a close relationship," Capstick told AFP.
"Rather I'd say it's an early successful relationship."
Trump commended Canada twice in his maiden address to Congress late last month, after heaping praise on Trudeau during his earlier visit to Washington.
"America is deeply fortunate to have a neighbor like Canada," Trump told a joint press conference with Trudeau at his side.
How Trudeau won over Trump
Canada and the United States share one of the world's longest borders, a highly integrated economy, and have common history and culture.
To ensure and bolster cooperation with Team Trump, Trudeau has quickly sent his top ministers to Washington to meet their new counterparts.
He has even gone as far as to recruit a former conservative prime minister and Trump friend, Brian Mulroney, to help build good relations.
"There are certainly some Liberals who aren't big fans of Mulroney but would acknowledge that he seems to have a skill for working with American politicians," former Liberal strategist Tim Powers told AFP, recalling Mulroney's camaraderie with Ronald Reagan.
Powers said there are people, including in Trudeau's own party, "who would like Trudeau to go after Trump for some of his behavior and statements", for example, those demeaning to women and Muslims.
Canada is the feeling the effects of the US's immigration ban along its border as an increasing number of refugees try to flee the US. Source: AAP
"But Trudeau helping Trump helps Canada," he said, adding that Trudeau was "smart not going after Trump, as other leaders did, during the American election campaign... I think it was noticed by the US."
"Wisely, he isn't letting ideological differences affect how he deals with Trump," echoed University of Toronto politics professor Ryan Hurl.
Trudeau has acknowledged the two leaders' vastly different worldviews.
"We won't always agree on everything," he said during his Washington visit.
But, he added, "the last thing Canadians expect is for me to come down and lecture another country on how they choose to govern themselves."
Rather, he suggested, it is better to "be a positive example in the world."
Risky courtship
Polls show Trudeau continues to be one of Canada's most popular leaders ever, both at home and abroad.
But experts say there are tremendous risks in courting Trump.
"We can't predict from moment to moment when something might offend Trump," said Robert Bothwell, a professor at the Munk School of Global Affairs in Toronto.
"There's no guarding against that and it could happen to anyone. I wouldn't say that Justin has any kind of magic immunity from that kind of situation."
Powers suggested that Trump "seems to recognize that our prime minister has political capital that can be helpful to him."
"Trudeau is well regarded in different parts of the world and for some of America's allies to see Trump and Trudeau get along helps Trump," he said.
On the flip side, according to Capstick, "if President Trump were to go after Canada too aggressively, the prime minister has the entire progressive world behind him and can rally a considerable amount of difficulty for Trump's politics."
