Speaker of the House Nancy Pelosi rips up the speech after President Donald J. Trump concludes delivering the State of the Union address from the House chamber of the United States Capitol in Washington on Feb 4, 2020.
Members of the U.S. House of Representatives officially elected Rep. Nancy Pelosi, D-CA as the first woman Speaker of the House on Jan. 4, 2007. House Minority leader John Boehner, R-OH presented her with the Speaker's Gavel.

WASHINGTON − Nearly four decades after she arrived in town, Nancy Pelosi is ready to head home.

"Dear San Francisco," she began in a soft-focus video posted on social media showing scenes of her adopted city. "I want you, my fellow San Franciscans, to be the first to know: I will not be seeking reelection to Congress. With a grateful heart, I look forward to my final year of service as your proud representative."

The former House speaker retires still holding the record as the most powerful woman in the history of the United States. While former Vice President Kamala Harris ranked one step closer in succession to the presidency, she never wielded the political and policy muscle that Pelosi did during two stints as the highest-ranking official in one of the three co-equal branches of government.

"Article One," she liked to remind people, citing Congress' primacy of place in the Constitution − ahead of the executive branch, established by Article Two.

She chose a high point to announce her departure, two days after California voters passed by nearly 2-1 a referendum that clears the way for the nation's largest state to redraw its congressional districts in an effort to oust five Republican incumbents.

That was just the sort of aggressive, push-the-envelope sort of politics that marked her approach from the start.

"Nobody's going to give you power," she would advise ambitious young Democrats. "You have to take it." That's what she did when she forced her way into the Democratic congressional leadership in 2001 in the face of dismissal and disdain by many of the men in charge.

"Nancy looks like a well-to-do San Francisco liberal," former President Barack Obama once told me, "but Nancy's a Baltimore kid who learned politics and policy from the old school."

Her first election victory, thanks to GOP votes

She was the daughter of Baltimore Mayor "Tommy the Elder" D'Alesandro Jr. and his wife, "Big Nancy," who ran his political operation from their rowhouse in the city's Little Italy. Hours after she was born, a photo of her in her mother's arms was splashed across four columns in the Baltimore News-Post. Her father and her five brothers were shown watching in apparent admiration.

"It's A Girl for the D'Alesandros," the headline read.

She grew up sitting next to her mother engaged in the most granular sort of politics, recording chits given and received from constituents in a process aptly named the Favor File.

But Nancy Patricia D'Alesandro Pelosi was 47 years old before she ran for office herself, after rearing five children and working as a fundraiser, organizer and state party chair in California, her adopted state.

In 1987, her first election to Congress in a special election was hard-fought and close, and she prevailed by convincing a small but crucial group of Republican voters that they would find her less intolerable than her more liberal Democratic rivals.

In 18 elections since then, she has had no significant trouble holding on to San Francisco's House seat. But at age 85, speculation was becoming louder that it was time to let a new generation take charge. State Rep. Scott Wiener already had announced he planned to run for her seat whether or not she sought a 20th term.

Pelosi told me she seriously contemplated announcing her retirement once the 2016 election had put the first woman, Hillary Rodham Clinton, in the White House.

Instead, Republican Donald Trump unexpectedly won that race and fueled her determination to stay. She would press impeachment proceedings against him − twice. In 2020, she was so enraged by his State of the Union address that after it was over she stood behind him and theatrically ripped her copy of it to shreds.

A year later, some in the Jan. 6 mob that assaulted the Capitol, trying to overturn Trump's 2020 election loss, targeted her, shouting "Where are you, Nancy?" and "All we want is Pelosi."

Now, to her dismay, Trump remains in power even as she leaves.

"He's just a vile creature," she said on CNN Nov. 3. "The worst thing on the face of the Earth."

A nemesis for George W. Bush, and a rescuer

She was the political nemesis not only of Trump but also of another Republican president, George W. Bush. As House whip, she was the highest-ranking Democrat to oppose the invasion of Iraq from the start.

But she also engineered Bush's rescue when the financial meltdown in 2008 threatened to bring down the U.S. and world economy. She played the crucial role in passing emergency financial legislation credited by economists with averting another Great Depression.

There was a political cost. She believed that blowback from voters angry that bankers got bailed out but not the millions of Americans who had lost their homes contributed to Democrats' loss of the House in the next midterm election − and with that, her role as speaker for eight years.

She was also the most influential legislative force behind enactment of Obama's signature law, the Affordable Care Act. She persuaded reluctant White House aides to go big, then maneuvered the legislation to passage under odds many saw as impossible.

It was the biggest expansion of health care for Americans in a half-century and her proudest legislative achievement.

She was instrumental in enacting key elements of President Joe Biden's agenda while Democrats controlled Congress during the first two years of his term. But she also engineered pressure on him to withdraw his bid for reelection in 2024 amid escalating concern about his capacity to wage a campaign and serve another four years.

In the ranks of Sam Rayburn and Lyndon Johnson

Pelosi is a fierce partisan and sometimes a brittle one, open to caricature by her foes. She raised money for Democratic candidates; depictions of her as a radical leftist raised money for Republican ones, too.

They also contributed to tragedy.

In 2022, a man broke into her San Francisco home, demanding to see her and assaulting her husband, Paul, with a hammer. In an echo of Jan. 6, the intruder shouted, "Where's Nancy?" Paul Pelosi was grievously injured but survived.

Pelosi's prowess at fundraising, her precision in counting votes and her formidable political memory made her not only a groundbreaking female legislator but one of the most consequential congressional leaders in the nation's history, in the company of Sam Rayburn and Lyndon Johnson.

"I think she has been one of the most significant figures in modern American history," said Hillary Clinton, herself a former first lady, U.S. senator, secretary of state and Democratic presidential nominee. "She has proven to be one of the most historically significant speakers in American history."

In the video, Pelosi thanked the citizens of San Francisco for electing and reelecting her.

"You enabled me to shatter the glass ceiling and become the first woman speaker of the House," she said. "We have made history."

Susan Page, Washington Bureau chief of USA TODAY, is the author of "Madam Speaker: Nancy Pelosi and the Lessons of Power."

This article originally appeared on USA TODAY: Nancy Pelosi's 'old school' career in Congress, from Obamacare to impeachment

Reporting by Susan Page, USA TODAY / USA TODAY

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