Editor’s Note: Kate Andersen Brower is a CNN contributor and the author of the book “Team of Five: The Presidents Club in the Age of Trump,” “First Women: The Grace and Power of America’s Modern First Ladies,” “First in Line: Presidents, Vice Presidents and the Pursuit of Power,” and “The Residence: Inside the Private World of the White House.” The opinions expressed here are hers. View more opinion articles on CNN.

CNN  — 

What Michelle Obama did at the Democratic National Convention Monday night has forever changed the way that former first ladies will use their tremendous influence during campaigns.

Kate Brower

No other one, including Hillary Clinton, has spoken so passionately about unseating an incumbent. What Obama delivered was not just a speech, it was a desperate plea. “If we have any hope of ending this chaos, we have got to vote for Joe Biden like our lives depend on it,” she said

“He cannot meet this moment,” she said, speaking of President Donald Trump. “He simply cannot be who we need him to be for us,” adding, for rueful good measure: “It is what it is.” When Obama, almost four years out of the White House, told the country that “enough of you know me by now,” she was drawing on her eight years as first lady as proof that she can be trusted.

“You know that I tell you exactly what I’m feeling,” she said. “You know I hate politics. But you also know that I care about this nation. You know how much I care about all of our children. So if you take one thing from my words tonight, it is this: if you think things cannot possibly get worse, trust me, they can; and they will if we don’t make a change in this election.”

Imagine Laura Bush talking with such searing intensity about President Barack Obama when he ran for re-election in 2012, or even Hillary Clinton, who ran for president twice herself, pleading with voters in such a way when John Kerry ran against George W. Bush in 2004.

Instead, at the 2004 Democratic Convention, Clinton, who would become the only former first lady to ever run for office, talked about health care and better pay and benefits for veterans in what now seems like a tame attack on Bush. “Do you know what we need to meet these challenges? We need a new commander-in-chief named John Kerry,” she said. “I’ve been saying for many months now John Kerry is a serious man for a serious job in a serious time in our country’s history.”

It was no frantic plea and she certainly did not paint the picture of a dystopian America under Bush that Obama painted Monday night as she warned of a second Trump term. Clinton gave a very conventional political speech.

Laura Bush (and her husband George) did not even attend the 2012 Republican National Convention where Mitt Romney was nominated. In an interview before the convention Laura Bush said that criticism of her husband’s eight years in office “doesn’t bother us.”

“We know what politics is like,” she said. “We know that, you know, people love to blame somebody else. That’s just a fact of life in politics…I think George makes an easy target.”

Indeed, the relationship between the Bushes and the Obamas offers a stark contrast to that of Trump and any of his predecessors. “This needs to be perfect,” Michelle Obama told her East Wing aides ahead of George W. Bush and Laura Bush’s 2012 visit to the White House for the official unveiling of their portraits, as I wrote in my book, “Team of Five: The Presidents Club in the Age of Trump.”

“It was the first time they had been back to the house they had lived in for eight years. The residence staff, at Michelle Obama’s direction, had a long table set in the elegant Red Room, on the State Floor, for the Bushes’ large extended family. Fourteen Bushes had a meal together and were served by the same butlers who had attended to them for years in the upstairs residence.” After the event, staff who worked for the Bushes gathered in the East Room in a receiving line to see them again.

Before Barbara Bush’s April 2018 funeral at her beloved St. Martin’s Episcopal Church in Houston, George W. Bush hosted a brunch for VIPs. “He was effusive about greeting everyone, but it’s possible that Michelle Obama got the biggest hug of all,” said George H. W. Bush’s chief of staff, Jean Becker, of the friendship between the Democratic former first lady from the South Side of Chicago and the former president from the country’s most prominent Republican family. When I asked if Michelle Obama and George W. Bush have become friends, Becker said without hesitation, “They have become best friends.” Obama has described Bush as a “beautiful, funny, kind, sweet man.”

She shares no such warmth with her husband’s successor. During her convention speech Monday Michelle Obama all but begged voters to make sure their votes were counted.

She said that the America that the Obamas’ two daughters see every day is “not just disappointing; it’s downright infuriating.”

In 2016 Michelle Obama famously stirred crowds when she responded to Trump’s campaign with the rallying cry “When they go low, we go high.” But more than three-and-a-half years of Trump’s presidency has made her change her approach.

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    “Going high does not mean putting on a smile and saying nice things when confronted by viciousness and cruelty. Going high means taking the harder path. It means scraping and clawing our way to that mountain top,” Obama said Monday night.

    The focus of her remarks was not Joe Biden and his running mate, Kamala Harris, the first Black woman ever on a major party ticket. It was all about getting Trump out, and as a former first lady her words matter.

    Clarification: This piece has been updated to clarify that Barbara Bush died in April of 2018.