Analysis by Maeve Reston, CNN

(CNN) -- Former first lady Michelle Obama's speech at the Democratic National Convention was not just a powerful condemnation of President Donald Trump's record and handling of the pandemic, it was an appeal aimed at the heart and conscience of every American who has watched the chaos of the last four years and yearned to make things right.

Reprising her role as "the closer" -- this time for former Vice President Joe Biden on the convention's opening night -- Obama spoke as the wife of a former President who has seen "the immense weight and awesome power" of the presidency up close. She spoke as a mother trying to teach empathy and instill "a strong moral foundation" in her daughters. And she spoke as an American pained "to see so many people hurting" at a time when the coronavirus has claimed more than 170,000 lives in the US and cast millions into unemployment.

On a night when many convention speakers, including four Republicans, tried to convince Americans of all political persuasions that they should choose country over party, Obama urged them to choose right over wrong, reminding her audience that she hates politics and asked all of her listeners to "close out the noise and the fear" and open their hearts. Those who do that, she said, "know that what's going on in this country is just not right."

The 18-minute address represented one of the most effective moral arguments against Trump's presidency from a prominent Democrat -- and came with a stark warning from the former first lady.

"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. 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 in a pre-taped address.

"Let me be as honest and clear as I possibly can. Donald Trump is the wrong president for our country," the former first lady said, faulting the President for downplaying the virus, stoking racial tensions, separating families at the border and exhibiting almost no empathy for the grief and loss that so many Americans have experienced.

She had harsh words for the President's derisive attempts to label demonstrators protested Floyd's death as "THUGS" who present a threat to Americans' way of life and called him out for coddling white supremacists in Charlottesville, Virginia. And she faulted Trump for refusing to acknowledge the racism inherent in American policing as a "never-ending list of innocent people of color continue to be murdered," while "stating the simple fact that a Black life matters is still met with derision from the nation's highest office."

America's children, she said, "see our leaders labeling fellow citizens enemies of the state while emboldening torch-bearing white supremacists. They watch in horror as children are torn from their families and thrown into cages, and pepper spray and rubber bullets are used on peaceful protesters for a photo-op. Sadly, this is the America that is on display for the next generation — a nation that's underperforming not simply on matters of policy but on matters of character."

America's children are seeing this White House promote greed, an "entitlement that says only certain people belong here" and the notion that "winning is everything, because as long as you come out on top, it doesn't matter what happens to everyone else," Obama added.

"He has had more than enough time to prove that he can do the job, but he is clearly in over his head. He cannot meet this moment. He simply cannot be who we need him to be for us," she said, before invoking Trump's callous response when asked about lives lost from coronavirus in this country: "It is what it is."

Obama wrote the speech with the assistance of a speechwriter and practiced it for weeks and the remarks were "immensely personal for her," an Obama aide told CNN. While the speechwriter helped, the former first lady knew clearly what she wanted to say, despite wishing to avoid dipping her toe back into politics, the aide said.

Obama's speech was taped before Kamala Harris was picked as Biden's vice presidential nominee, according to an Obama adviser, and she did not mention Harris in her remarks.

Obama tried to serve as a character witness for Biden, making an explicit contrast between Trump and the man who served alongside her husband for eight years. She noted that the job of president requires "clear-headed judgment, a mastery of complex and competing issues, a devotion to facts and history, a moral compass and an ability to listen," adding that a president must believe that each life in this country has "meaning and worth."

Biden understands the losses that many Americans are facing, she said, because he has lived through some of them himself -- from the days when Biden's father struggled to provide for his children, to the loss of his first wife and young daughter in a car crash in 1972, to his grief and anguish losing his son Beau Biden at the age of 46 to brain cancer just five years ago.

"Whenever we look to this White House for some leadership or consolation or any semblance of steadiness, what we get instead is chaos, division, and a total and utter lack of empathy," Obama said.

"Joe knows the anguish of sitting at a table with an empty chair, which is why he gives his time so freely to grieving parents," she continued. "His life is a testament to getting back up, and he is going to channel that same grit and passion to pick us all up, to help us heal and guide us forward."

Perhaps Obama's most famous quote came during her 2016 convention speech -- "when they go low, we go high." During Trump's presidency, she said, many people have asked "when others are going so low, does going high still really work?"

"My answer: going high is the only thing that works, because when we go low, when we use those same tactics of degrading and dehumanizing others, we just become part of the ugly noise that's drowning out everything else," she said. "We degrade ourselves. We degrade the very causes for which we fight."

At a time when the US Postal Service is under attack and there are lawsuits and legal hurdles being thrown up all over the nation that would limit the right to vote, Obama encouraged her listeners to vote early, in person or "request our mail-in ballots right now, tonight, and send them back immediately and follow-up to make sure they're received" and then make friends and family do the same.

"We have got to grab our comfortable shoes, put on our masks, pack a brown bag dinner and maybe breakfast too, because we've got to be willing to stand in line all night if we have to," she said.

She urged Democrats to marshal the same level of passion they did in 2008 and 2012 and made a plea to leave no doubt about the margin of the election: "Vote for Joe Biden in numbers that cannot be ignored."