The PM made history again when he became the first sitting prime minister to participate in another more understated, but equally important celebration: the Halifax Pride parade.
Some say Trudeau is all style and no substance. This may be true, but sometimes style counts for a great deal.
Thanks to the PM, norms are slowly shifting to a point where it's standard for a prime minister to attend not only a major city's Pride celebration, but a smaller city's celebration as well: a city such as Halifax, where Pride isn't an international tourist draw.
This means that when someone new is elected to the office of prime minister - a Conservative perhaps - the national expectation around major Pride events will be one of attendance.
It will be unusual for a sitting PM to skip a well-known city's Pride parade, not commonplace. This is a good thing. This is real-world progress that you can see with your own two eyes and applaud.
Or, if like a number of LGBTQ activists in this country you're determined to be miserable until the day you die, you can lament Trudeau's presence at Pride instead, and label it "pinkwashing" - the LGBTQ equivalent of "whitewashing."
Not everybody thought Trudeau's attendance at the Halifax parade was a wholly positive thing. Some, such as Kehisha Wilmot, head of Halifax's Mount Saint Vincent University Queer Collective, believe Trudeau's participation was a distraction from the event's more marginalized participants.
"We have people of colour doing things in this parade," Wilmot told Halifax magazine The Coast this week, in a story headlined "Trudeau Pinkwashing Pride parade."
"And the big thing we're currently now looking at is we brought down a white guy in a high-position role to be our focus."
I don't want to diminish the work done by groups such as Wilmot's because it is important work. Yet a reminder is in order that a world leader's presence at an event does not impede activists from making their voices heard.
Trudeau was in attendance at Toronto's Pride parade in 2016, where Black Lives Matter Toronto managed not only to stage a successful protest that effected tangible change, but to dominate media coverage in the event's aftermath.
Moreover, these activists are ever eager to identify privilege in other people, but they are utterly blind to the privilege they enjoy themselves: they have integrated into a community of like-minded people. Yes, they are marginalized in society at large, but they have found a place where they belong.
Not everyone enjoys this privilege. Take, for example, my friend Yvonne Jele, a gay refugee from Uganda, who is practically brand new to Canada (she fled her native country last year). Jele, who lives in Toronto, was overjoyed when she learned that the leader of her new home was marching in her city's Pride parade.
"People who are mad (that Trudeau participates in Pride events) don't know what it's like to not be accepted by your leaders and government," she told me recently.
Jele has some thoughts about corporate interests in Pride, too: "I think everyone can show support during Pride," she said. "It's important for businesses to do so because it shows that the business is inclusive."
These broad gestures of support by politicians and businesses matter a great amount to people who aren't yet integrated into a tight-knit queer community, and they matter to closeted kids who are watching and reading about Pride from a distance, absent the support of such a community.
It's a very good thing for these kids to know that their banks, hardware stores, coffee shops, internet providers and, yes, their leaders, take a public stance in favour of their rights.
No, these businesses and politicians aren't by any means perfect. Yes, some of them make errors and false promises.
But their participation in Pride parades across the country is a gesture of goodwill felt deeply by those who have not yet found their home away from home.
The prime minister's presence at Halifax Pride will not matter most to the out and proud, but to LGBTQ people who are neither. And the activism of the former should not extinguish the hopes of the latter.
Emma Teitel is a national affairs columnist for Torstar Syndication Services.