Justin Trudeau’s announcement on Monday that he would resign was the last card that Canada’s deeply unpopular prime minister, who had set his party on course to lose a national election, had left to play.

The political levers he has pulled will give Mr. Trudeau’s Liberal Party a chance to reinvent itself without him. But they will also leave Canada weakened as it braces for President-elect Donald J. Trump, who has threatened the country with tariffs that could cripple its economy.

It appears to be a gamble that Mr. Trudeau is willing to take.

To allow his party’s thousands of members to choose his successor, a lengthy process that will involve campaigning, Mr. Trudeau suspended Parliament until March 24. A general election is expected to follow.

Holding a party leadership election before a general one is par for the course in countries with parliamentary systems like Canada’s. Suspending Parliament to hold such an election is far less common. By doing so, Mr. Trudeau wards off the likely collapse of his minority government and gives the Liberals time to choose a leader unburdened by his dismal poll numbers.

But it means that in two weeks, when Mr. Trump returns to the Oval Office, Mr. Trudeau will be leading Canada as a lame duck, weakening the country’s hand in crucial negotiations with its closest ally.

“The prime minister stepping down means it will be hard for him to carry any meaningful mandate in negotiating with the U.S., and it doesn’t signal any unity within Canada,” said Xavier Delgado, a senior program associate at the Canada Institute of the Wilson Center, a Washington-based foreign policy research institute. “It’s not a great time for Canada to be in this situation.”

Mr. Trudeau’s opponents wanted a quick general election, which would let a new government with a fresh mandate — presumably led by Pierre Poilievre, whose Conservative Party has a commanding lead in polls — spearhead Canada’s response to Mr. Trump as soon as possible.

Mr. Trump has threatened to slap punishing tariffs on Canadian goods that could send the country’s economy into a recession and upend the North American trade pact established over the past few decades. (It would also be injurious to the U.S. economy; the two nations are each other’s biggest trading partners.)

The president-elect has persistently suggested that Canada should become part of the United States, calling it the “51st state.” He repeated his menacing joke on social media on Monday, after Mr. Trudeau’s resignation announcement: “Many people in Canada LOVE being the 51st State,” Mr. Trump said in a post on Truth Social, promising no tariffs if Canada “merged with the U.S.”

Party first

When Mr. Trudeau became the Liberals’ leader, the party was in shambles. In the 2011 national elections, it finished third for the first time in its history. Mr. Trudeau, who assumed its leadership in 2013, is widely credited with raising it from the dead and leading it back into government two years later.

“The Liberal Party, such as it is, has been the Justin Trudeau party for more than a decade,” said Shachi Kurl, president of the Angus Reid Institute, a research center. That has made it hard for the party to let go of him and for Mr. Trudeau to relinquish control, Ms. Kurl said.

But finally, on Monday morning, after weeks of pressure from within the party to resign, Mr. Trudeau acknowledged that his time was up.

“I truly feel that removing the contention around my own continued leadership is an opportunity to bring the temperature down,” he told reporters gathered in the freezing cold outside his Ottawa residence.

“It’s become obvious to me with the internal battles that I cannot be the one to carry the Liberal standard into the next election,” he added. Until the Liberals choose their new leader, Mr. Trudeau said, he will stay on in that role and as prime minister.

The party’s internal election process, which will last several weeks, will allow a handful of hopefuls to reintroduce themselves to the public, no longer as Trudeau associates but as individuals vying for the party’s and the country’s leadership.

“I think the Liberals are now clinging to the idea that there is no longer a path forward for him, but there is absolutely a path forward for someone else,” Ms. Kurl said.

Still, with the Conservatives leading the Liberals by 25 percentage points in recent surveys, the path that Mr. Trudeau bequeaths his successor is likely to be treacherous.

“Sixty or 90 days are not a long time to reinvent a party after 10 years in power,” Ms. Kurl said. “How many more rabbits are in the hat? How many more pivots are there?”

Brief relief

For many Canadians, Mr. Trudeau’s departure was a necessary condition if they were going to consider voting for the Liberals.

David Coletto, who leads Abacus Data, a polling company, said early research on Monday suggested that Canadians felt relief at the news of Mr. Trudeau’s resignation, and that his departure had the potential to shift attention away from his unpopularity.

“People are saying they feel relieved and optimistic about the prime minister stepping down,’’ he said. “That’s a signal to me that there’s potentially an opportunity for the Liberals to rebuild the relationship with Canadians.” But it is far from certain that this will happen, he cautioned.

While Mr. Trudeau’s departure can only improve the Liberals’ situation, analysts said, the country is unlikely to benefit from being practically leaderless as Mr. Trump takes office.

As the new president begins to push through his agenda — which has Canada in its cross hairs, with Mr. Trump having complained about border security, Canadian military spending and a trade imbalance — Canada will be trying to sort out who’s in charge.

“Canada would be strongest in dealing with the United States if it could unify around the message for its leader — and that would apply to any country,” said Mr. Delgado of the Wilson Center’s Canada Institute.

Others were less concerned, suggesting that Canada’s dealings with the Trump administration would be a long game.

Gerald Butts, a former top adviser to Mr. Trudeau who is now vice president at Eurasia Group, a consulting firm, said no leader would be able to cut a deal with Mr. Trump on Day 1.

“Nothing irreparably bad will happen in the next three months,” Mr. Butts said. “We’re going to have Trump for four years; the next three months are not going to be the whole story.”

The business owners arrived one by one, but all were united in their mission on a chilly December morning: Salvage anything from the pulverized market in this hillside city in southern Lebanon.

A photo studio operator and his son trudged through debris and twisted metal to recover dust-coated negatives and camera lenses. A clothes shop proprietor dragged a garbage bag holding leggings, retrieved from under mangled rebar. And an optical store owner stood atop crushed concrete slabs that were once the rooftop of his business’s building.

“Everything is gone,” said Raed Mokaled, 58, who, along with the eyeglasses business, co-owned a gold and watches store in the same building with his brother. “An orange ball of fire took out everything.”

Israel conducted intense air raids and then began a ground invasion into south Lebanon in late September to retaliate against Hezbollah, the Lebanese militant group that had been attacking it in solidarity with Hamas after the Oct. 7, 2023, terror attacks on Israel. A fragile 60-day truce, signed in November, has suspended the conflict between Israel and Hezbollah.

In the city of Nabatieh, which shares its name with the surrounding governorate where Hezbollah largely held sway, Israeli strikes obliterated the historic market on Oct. 12, at the height of the war. Another strike hit the nearby municipal building a few days later, killing at least 16 people, including the city’s mayor, according to Lebanese officials.

Israel said it had attacked Hezbollah targets in the area, but its claim could not be independently confirmed. Amnesty International said it did not find any evidence of a military target at the city’s headquarters.

The strikes across the governorate, which borders both Israel and Syria, have left behind scenes of desolation and ruin that many Lebanese say are unlike any they have seen. A World Bank report estimated the Nabatieh governorate incurred $1.5 billion in economic losses during the war with Israel.

On a recent morning, two weeks after the cease-fire, reporters with The New York Times arrived in the market as residents and business owners came to survey and deal with the wreckage. One by one, they said, they drove across rutted and bombed-out roads to arrive at the centuries-old market they fondly called the souk. Once a bustling center for vendors and shoppers from across Lebanon, it was now a shell of its glorious past.

Iconic shops, like the decades-old sweets store, were wiped out. Collapsed walls, shattered glass and twisted steel lay everywhere. Instead of the fragrant herbs and fresh produce that many people once sought in the market, a smoky and charred smell still swirled in the air.

Mannequins perched atop the mound of rubble and wires. Receipts, CDs and tattered sneakers littered the scorched pavements.

“This is a catastrophe,” said Niran Ali, 58, while standing amid the wreckage.

For 16 years, she co-owned a children’s clothing shop in the market and used it to support her family of four. Now, almost everything — about $100,000 in goods, she said — was gone.

“The destruction is painful to look at,” she said. “Our only hope is with God.”

Just across the street, Abed Al Raouf Farhat, 34, inspected the damage to his father’s photo studio. The strikes hadn’t entirely crumbled the building, but left it marred with deep cracks, exposed beams and a leaking roof. Inside, thick dust coated everything: the damaged photocopier, the cameras, the wooden photo frames.

Mr. Farhat’s father, Hamzah, opened the Amal Photo Studio Lab in 1982. Since then, generations of families across Nabatieh had been coming to take wedding and graduation photos. The elder Mr. Farhat, who is 65, also trained young photographers — including his own son, who has since gone to work as a photographer and videographer across the Middle East and Africa.

With the damage from the latest strikes, Mr. Farhat said, an establishment that was a symbol of community and collective memory has become a grim reminder of the war’s heavy toll. “Everything is gone,” Mr. Farhat said. “But my dad and Nabatieh are still standing, and he will start again from zero.”

The photo studio’s story — and the larger market’s — is closely intertwined with the city’s tumultuous past. Israel attacked Nabatieh in 1974 and 1978 and occupied it for three years beginning in 1982 following its invasion of southern Lebanon in retaliation for the Palestine Liberation Organization’s shelling of northern Israel. It also bombarded Nabatieh in 1993, 1996 and during the monthlong 2006 war as it clashed with Hezbollah in the region.

Hezbollah is a dominant force in Nabatieh, which has a majority Shiite population, though the group doesn’t have unanimous public backing. In several streets across the city, images of Hassan Nasrallah, the Hezbollah leader assassinated by Israel in September, are pasted on walls and electricity poles.

When Israel attacked the market in 2006, business owners said the Iran-backed group gave them some money to rebuild. This time — with Hezbollah weakened, its military abilities and infrastructure degraded and its ally in Syria deposed — no one had approached them to make assessments or lend support, several business owners said.

Hezbollah announced in late December that it had a program to rebuild the southern villages pummeled by Israeli raids. Hezbollah officials said priority would be given to families whose homes were completely or partly destroyed, but didn’t say when or if businesses would get financial support.

Hezbollah also said the task of reconstruction was a national one and that the state — over which it holds significant power — also had a responsibility to help citizens rebuild.

“Every few years, we lose everything,” said Khalil Tarhini, 67, whose lingerie and underwear shop was flattened. When his shop was damaged in 2006, Hezbollah, he said, gave him $18,000 in compensation — a fraction of the more than $100,000 he lost, he said. He had to sell his property to rebuild the business, he said.

“We will be back, but it will take a while,” Mr. Tarhini said as he stared at bulldozers clearing debris where his shop once stood.

For now, the slow and grueling process of rebuilding has begun. Across Nabatieh, advertisements and signs in Arabic declare, “We will rebuild together,” or, “It will come back better.”

Hassan Jamal Sabboury and his family returned to the city from the capital, Beirut, hours after the cease-fire took effect in late November.

What he found, he said, brought him to tears. The gas station and carwash, which his grandfather first built decades ago, were gone. His apartment down the street, which he had outfitted with plush, cream-colored furniture, was ravaged.

But the strikes didn’t hit the fuel tanks underground, he said, allowing him the chance to restart somewhere.

“We are staying strong and resilient,” he said as he managed workers moving debris and mixing cement. He hoped the gas station would reopen in a month.

Mr. Mokaled, who ran the glasses business, was not so lucky.

When he and his family returned to the market, they realized they had lost goods worth hundreds of thousands of dollars. Glasses, eyewear repair kits and gold cleaning equipment were wrecked. Out of 1,200 watches in the store, they were able to recover just over 100, he said. His home was also hit in a strike, and he was now staying in a one-bedroom guesthouse.

Despite an overwhelming sense of disbelief, he said, he had no choice but to rebuild. He and his brother have rented another store and plan to restart the optical business on a smaller scale.

“Life has to go on,” he said, his face pale and drawn. “If you stop, that means you are dead.”