The week after Election Day in 2016, Shirley Morganelli, a women’s health nurse and lifelong Democrat, invited a dozen friends over to the living room of her rowhouse in Bethlehem, Pa., for a glass of wine. Actually, many glasses.

“Misery loves company,” she said.

Ms. Morganelli’s friends, mostly women then in their 50s and 60s, were teachers, nurses, artists and ardent supporters of Hillary Clinton. Some of them had dressed in suffragist white to cast their votes that day, expecting to celebrate the election of America’s first female president. Instead, they had ended the night consoling their college-aged daughters.

“When she called me at three o’clock in the morning — I get all choked up now, because it was the first time I couldn’t say, ‘Everything’s going to be all right,’” said Angela Sinkler, a nurse and former school board member in Bethlehem.

The get-together — Ms. Morganelli called it “unhappy hour” — became a regular event. By the end of the month, commiserating had turned into organizing. They started with writing postcards to elected officials calling on them to oppose Donald J. Trump’s agenda, then moved on to raising money for a local Planned Parenthood chapter and joining in community protests.

Local political candidates began showing up to their gatherings, too, and the group, now called Lehigh Valley ROAR, turned to campaigning. In 2018, several members were elected to City Council in Bethlehem, and Susan Wild, the city solicitor in nearby Allentown and old friend of Ms. Morganelli’s, was elected to Congress with the group’s support.

Lehigh Valley ROAR was one of more than 2,000 similar grass-roots groups formed in the wake of Mr. Trump’s first election — a moment of mass organization larger than even the Tea Party movement at its peak during President Barack Obama’s first term, said Theda Skocpol, a Harvard University professor of government and sociology who has studied both movements.

A vast majority of the groups were led by women, and many traced a similar arc to Ms. Morganelli’s, their shock at Mr. Trump’s election sparking political activism and then, often, electoral victories.

But then there was the defeat of Vice President Kamala Harris in November.

As Mr. Trump returns to the White House on Monday with a popular vote majority and a governing trifecta in Washington, there are few signs of the sort of mass public protest that birthed “the resistance” the last time he took office.

Mr. Trump’s inauguration in 2017 was met with the largest single-day public demonstration in American history. Although thousands marched in Washington Saturday and smaller protests were held in other cities, their numbers fell far short of the hundreds of thousands that rallied eight years ago.

Organizers of the 2017 efforts say this shift reflects the lessons learned from the street protests that took place early in the first Trump presidency, tactics that were quickly abandoned in favor of more strategic organizing — and that opposition to a second Trump term is unlikely to take the same forms.

But some concede that the opposition is more uncertain than it once was. Congressional Democrats and governors now openly debate the wisdom of locking arms against Mr. Trump’s agenda, as they eventually did during his first presidency. And Democrats still now bear scars from last year’s conflicts over Israel’s invasions of Gaza and Lebanon, their embrace of identity politics and President Biden’s aborted candidacy.

In 2017, “everything felt bigger, more important,” said Krista Suh, a screenwriter in Los Angeles. When the Women’s March was announced for the day after Mr. Trump’s swearing-in, Ms. Suh, a novice knitter, came up with a pattern for a cat-eared pink cap to wear to the protest and posted it online.

Within days, “pussy hats” became a ubiquitous emblem of anti-Trump dissent.

Ms. Suh has stayed somewhat politically involved; she canvassed for Ms. Harris in Arizona. But she had no plans to protest this weekend.

“I feel like I’m just so much more jaded now,” she said.

‘He Won the Popular Vote’

When members of Lehigh Valley ROAR assembled once again in Ms. Morganelli’s living room this month, days before Mr. Trump would return to the White House, few were certain about what they should do next. They had canvassed and phone-banked for Ms. Harris. “You name it, we did it,” Ms. Morganelli said.

Ms. Wild had lost her seat, too.

In the corner of Ms. Morganelli’s living room, a cardboard cutout of Mr. Obama still wore a pink hat from the 2017 Women’s March, which most of the group members had attended. But none of them were going to Washington to protest Mr. Trump’s inauguration.

Some members had come to question the effectiveness of the Women’s March. Others were now more concerned about the safety of demonstrating. Last fall, one member’s car was broken into by someone who also tore up the Harris yard signs she had in the back seat.

Four years after the Capitol riot on Jan. 6, 2021, Ms. Morganelli was ambivalent about the optics of protesting the outcome of a fair election.

“This time, he won the popular vote,” she said, referring to the president-elect. “As good Americans and good Democrats, you have to accept that, right?”

Instead of protest, the group planned to get together to drink wine and write thank-you notes to Mr. Biden. “Moving forward, all we can do is try to be our best selves as good citizens,” Ms. Morganelli wrote on the group’s Facebook page.

A Resistance With Some Regrets

In its early days, the opposition to Mr. Trump seemed to practically organize itself. Grieving liberals poured their energy into any vessel available. People who had never organized a protest in their lives were transformed into leaders of demonstrations of historic scale, sometimes overnight, as was the case for Naomi Lindquester.

Jolted by Mr. Trump’s election, Ms. Lindquester, then a 42-year-old elementary schoolteacher in Denver, created a Facebook event called Women’s March on Denver. She thought she would have to beg her friends to attend.

Instead, the day after Mr. Trump’s inauguration, a crowd estimated at more than 100,000 people arrived at the State Capitol to denounce the new president. It was likely the largest demonstration in the history of Colorado.

The Women’s March protests drew some 500,000 attendees to Washington and hundreds of thousands more rallied across the country. But the groups that materialized to organize them, often led by media-savvy young urban professionals, soon found themselves struggling to maintain momentum and, at times, infighting.

The national Women’s March organization splintered after one organizer accused others of antisemitism. Other groups disintegrated amid more prosaic conflicts over priorities and egos.

“It got really ugly, really fast,” said Ms. Lindquester, who has not spoken with her fellow organizers of the Denver march since they fell out in late 2018.

Many such groups, she believes, were victims of their sudden celebrity. “I’ll be really honest with you,” she said, “I very much enjoyed my 15 minutes of fame.”

Since November, Ms. Lindquester has found herself questioning the impact of the march she organized. “The fact that we did that ginormous march and he still got re-elected a second time?” she said.

She has mostly stepped back from public politics — a shift that was in part a result of her move from Denver to a small, conservative town elsewhere in the state, and the heightened scrutiny on teachers’ politics in recent years.

While she was proud of her role in the 2017 protest, “I don’t talk to anyone about that, because I will hear about it if I do,” she said.

In a Facebook post this month she suggested a list of actions that she argued would make a bigger difference now than marching: Plant trees. Volunteer in the community. “Engage with people who think differently than you and find your common ground.”

A New Message: ‘This Is Hard.’

Some argue that the energy is still out there, but the goals are different. Ezra Levin, the executive director of Indivisible, an organization he co-founded in 2017 to channel grass-roots opposition to Mr. Trump, said the group had registered more new local chapters since November than it had at any other point since 2017.

In a new blueprint for action released shortly after the election, Indivisible urged its members to focus not just on Mr. Trump and Congress but also on local elected officials — particularly Democrats in blue states that could serve as a bulwark for resisting Mr. Trump’s policies.

It conceded that “too often in Trump 1.0, we embraced the aesthetics of protests instead of using them as part of a strategy.”

“You shouldn’t start with a tactic,” Mr. Levin said. “You should start with a goal.”

In Ms. Morganelli’s living room, the Lehigh Valley ROAR members spoke of leaning on one another even more as some family members drifted away from their politics in recent years: children who had grown enamored with right-wing survivalism or opposition to vaccines during the coronavirus pandemic, or turned on Mr. Biden and Ms. Harris over their support for Israel.

“I lost my liberal, progressive son to Joe Rogan,” one said, as others nodded in sympathy.

They felt alienated from younger Democratic activists who seemed to see fighting Mr. Trump as a lesser priority than matters of ideological purity.

“If you’re not lefty-left enough, they are willing to sacrifice their vote and throw it away,” either by not voting or voting for a third-party candidate, said Lori McFarland, a member of the group who is now the chairwoman of the Lehigh County Democratic Committee. “And they’ve just set us back.”

Ms. Suh, the “pussy hat” creator, has not sought to reprise her role in the protest movement. She thought that a unifying phenomenon like her hat would still be possible — but the message should now be something different than the defiance of early 2017.

“I think,” she said, “it has to be something like: ‘I hear you. This is hard.’”