“I will win, I have absolutely no doubt.”

Justin Trudeau looked serene as he spoke the words. There was no hint of hubris, no sense he was spinning me with some empty rhetoric. He said it as if he were making an incontestable observation about the weather, that, say, snow would come in winter. He knew everyone doubted him. He spoke candidly about being regarded as a lightweight, someone not ready to get into a fight with a tough, veteran brawler. It was all, he explained, part of his strategy. “People expect me to lose, so if I do, there’s no downside to it.” Then he paused for a split second. “But I won’t lose. I’ve been training my whole life at this.”

It was March 28, 2012, two days before his boxing match with the (now suspended) Sen. Patrick Brazeau. The sun was bright overhead as we spoke on Parliament Hill under the Peace Tower. I wasn’t sure what to make of the conversation at the time, but I was struck by how carefully he had plotted it out, how strategically aware he was of the benefits of low expectations. Forty-eight hours later, he did exactly what he said he would do. He destroyed Brazeau.

Now, in the afterglow of Trudeau’s massive majority victory, that brief encounter has the penumbra of symbolism, and it’s tempting to elevate it as a kind of foreshadowing to his ascension and Stephen Harper’s demise. But Camelot-style myth-making is from a bygone era. Political battlegrounds are gored with “candidates of destiny” lying wounded on the field, watching their egos die.

Related: Trudeau in the ring: That night in Ottawa

There was nothing inevitable, nothing predetermined about Trudeau’s election win. It took a flawlessly executed, high-risk Liberal campaign, combined with a surprisingly narrow-minded, thuggish Conservative run, one that underestimated the antipathy toward Stephen Harper and his jacked-up politics of division. It also required the collapse of the NDP vote, whose strategists calamitously traded away Jack Layton’s optimism for Tom Mulcair’s dour pragmatism. The anatomy of the campaign has already been dissected—from the niqab effect to the economic promises—but it’s fair to say no one saw all these events coming together this way 81 days ago. After all, it takes a lot more than mere self-confidence to win a federal election.

Neither anecdotes nor elections reveal the true character of Justin Trudeau. Campaigns are, at best, Potemkin villages, facades painted with either negative stereotypes by opponents—“Just not ready”—or shellacked in shiny praise by supporters—“He will change everything.” For a politician, nothing reveals character more than the fundamental act of governing. It is slow, hard, grinding work, a process that might be fuelled by a vision and sunny optimism for change, but is eventually put through the shredder of realpolitik and the art of the possible. Even majority governments are seduced by the siren song of incrementalism, and get wrecked of the rocks of the status quo.

Over the last seven years, Barack Obama, whose initial campaign was really a kind of template for Trudeau’s, revealed the distance between soaring rhetoric and sluggish reality. Canada is not the same, of course; our majority governments do not succumb to the same kind of political sclerosis. But Trudeau’s real character will immediately be judged by his first decision, and that is selecting a cabinet.

Under Harper, the so-called “party of one,” in author Michael Harris’s phrase, a gelded cabinet bloated to 40 people. Trudeau has promised to make his smaller, but at his first press conference would not be specific about the size of the cabinet he will name on Nov. 4. But with more than 183 MPs to choose from, creating his cabinet will be an alchemy requiring a dash of geographic representation, a balance of gender, ethnic diversity and a mysterious system of reward for veterans and merit earned by star candidates.

For example, New Brunswick veteran MP, lawyer, and close Trudeau confidant Dominic LeBlanc might become the new justice minister. Veterans such as Ralph Goodale and Scott Brison have loads of experience in finance, but so does newly elected Bill Morneau, a former CEO who won Toronto Centre, and who was instrumental in developing the Liberal economic platform. And what about former business journalist and Rhodes scholar Chrystia Freeland? Could she be finance minister? Former TV broadcaster and close Trudeau friend Seamus O’Regan, from Newfoundland, might get Fisheries and Oceans. And what about former Toronto police chief, Bill Blair? Public safety? Andrew Leslie, the former Canadian Forces lieutenant-general and head of the Army, could get Defence. A star candidate from B.C., lawyer Jody Wilson-Raybould, formerly an Assembly of First Nations chief, might get a high-profile position. And where does Trudeau put the compelling star, Robert-Falcon Ouellette, a Cree from Winnipeg who unseated the NDP’s Pat Martin? There is also Harjit Singh Sajjan, a Sikh lieutenant-colonel who served and commanded in Afghanistan. He must have a role to play. Does Mark Holland, who took out Immigration Minister Chris Alexander, come back in, after four years in the cold? What about Mélanie Joly, who made her reputation as a popular candidate in the last mayoral race in Montreal?

Speculating about cabinet posts is the political equivalent of playing fantasy baseball, and usually the pundits—like me—are wrong. But cabinet appointments—along with fulfilling his initial promises, such as raising taxes on the rich, and cancelling the F-35—are the first real indications of the kind of leader Justin Trudeau will be. Campaigns can win on charisma. Governing must run on character.