Carl Bernstein, a CNN political commentator, is the author of "A Woman in Charge: The Life of Hillary Rodham Clinton," considered the definitive biography of its subject. The opinions expressed in this commentary are his

(CNN) Not coincidentally, Barack Obama has delivered what historians may judge the most important — and inspiring — speech of his presidency at the critical juncture of an election that in all likelihood will determine the future of America for generations.

And if Hillary Clinton is to succeed Obama as president, he will probably have to drag her across the finish line. How? By providing some credible perspective that — in keeping with the truly American values eloquently expressed this weekend in his dedication of the National Museum of African American History and Culture — vouches for the basic honor of her life and public service, whatever her considerable shortcomings as a presidential candidate. And by drawing a marked contrast between the life and (often un-American) values of Donald Trump.

Barack Obama's vision of America and its history — the story he told on the Mall Saturday — recognizes that the great struggle and inspiration of our nation since its founding has been over slavery and its legacy. It is his story. He evoked — perhaps as no speech has since Martin Luther King shared his dream just yards away 53 years ago — the agonizing and triumphant narrative of America, which more than anything else, is the story of a nation built by blacks and whites, and shaped by waves of immigration.

And that story turns out to be what this election is about.

Hillary Clinton, beginning in Monday's debate , must establish once and for all that her values and the story of her life and her politics have always been rooted in this vision of America, and never strayed; and make indelibly clear that Trump's vision — and all the danger it represents — is totally at odds with the American story told by Obama on Saturday.

"The best history helps us recognize the mistakes that we've made, and the dark corners of the human spirit that we need to guard against," Obama said. Trump's campaign is the exposition and exploitation of those dark corners.

Among the key sentences in the President's speech relevant to the debate and election, none were more important than these: "This museum alone will not alleviate poverty in every inner city, or every rural hamlet. It won't eliminate gun violence from all our neighborhoods, or immediately ensure that justice is always color blind. It won't wipe away every instance of discrimination in a job interview, or a sentencing hearing, or folks trying to rent an apartment. Those things are up to us, the decisions and choices we make."

In the era of civil rights progress following King's speech, Donald Trump walked in his father's footsteps of bigotry and exclusion to prevent blacks and Puerto Ricans from renting thousands of apartment units owned by the Trumps in the '70s in New York City, in violation of the Fair Housing Act of 1968. The testimony against Donald Trump's company to this effect is extensive and damning (though, in a consent agreement finally reached with the U.S. Department of Justice in 1975 to rent on a non-discriminatory basis, the Trump Organization did not admit to past discrimination).

In the instance of Fred and Donald Trump, the sins of the father also became the sins of the son. And they endure in his campaign and its underlying assumptions about America and Trump's misreading of its history. They are among the elemental facts at our command to understand Donald Trump — today and yesterday.

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Not Hillary Clinton. Hugh Rodham, her father, also embraced the bigotry of his era, and at the family dinner table routinely described blacks in the most demeaning and bigoted terms. But when Hillary was a teenager, a youth minister took her to hear Martin Luther King Jr. preach in Chicago. In college, her advocacy against racial discrimination on and off campus became increasingly activist, and since then, the constant of her public service and her political and cultural beliefs and advocacy has been about equality in every regard for all citizens, and an end to all forms of discrimination.

It is a straight line from the Trump family's rental policies to Donald Trump's campaign policies appealing to bigotry and racism and nativism. None of this is to deny the validity of his (or Bernie Sanders') recognition of the economic marginalization of so many working-class Americans over the past quarter-century, or the apparent blindness of the country's "elites" to their suffering.

"And so this museum provides context for the debate of our times, it illuminates them, and gives us some sense of how they evolved, and perhaps keeps them in proportion," Obama said Saturday.

Through much of this campaign, Hillary Clinton has been her own worst enemy, often failing to explain what truly motivates her quest for the White House.

Beginning in Monday's debate, Clinton needs to tell the story of her life over and over in the context of her advocacy for the kind of America Barack Obama summoned on Saturday.

The press, too, should reflect on the President's assertion of "context for the debate of our times," and the notion of "proportion" in describing and comparing the lives and records of the two candidates and their visions for America.

Obama also said:

"And that's what this museum explains, the fact that our stories have shaped every corner of our culture, the struggles for freedom that took place made our Constitution a real and living document, tested, and shaped, and deepened, and made more profound its meaning for all people.

"The story told here doesn't just belong to black Americans, it belongs to all Americans, for the African-American experience has been shaped just as much by Europeans and Asians and Native Americans and Latinos. We have informed each other. We are polyglot, a stew.

"Scripture promised that if we lift up the oppressed, that our light will rise in the darkness, and our night will become like the noonday. And the story contained in this museum makes those words prophecy. And that's what this day is about, that's what this museum's about."

And that's what the presidential election of 2016 is really about, as he implied.

The outright — and underlying — racism of Trump and his campaign will have to compete from now until November 8 against this vision of America laid out by Obama as the President campaigns intensely on Hillary Clinton's behalf in the remaining 42 days before the election, and notes her fealty to those ideals in a lifetime spent in the political arena. None of this is to deny some of her personal failures and shortcomings on such vivid display since she announced her campaign for the presidency and -- in some instances -- throughout her public life.

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In the end, this election is a choice between two different sets of values and visions for America and the real lives lived by the two candidates — not the self-created images or mythical lives of either. Again, the press needs to focus less on the horse race and more on the backgrounds and records of the horses before they got here.

"And so hopefully this museum can help us talk to each other," the president said. "And more importantly, listen to each other. And most importantly, see each other — black and white and Latino and Native American and Asian American — see how our stories are bound together. And bound together with women in America, and workers in America, and entrepreneurs in America, and LGBT Americans."

That has been the undertaking of Hillary Clinton's life — not Donald Trump's.

The closing paragraphs of "A Woman in Charge, The Life of Hillary Rodham Clinton" — hardly an uncritical biography of its subject, as the Clintons have made clear in their discomfort with the book — are about the opportunity that now lies before her, concluding:

"As a girl and then as a woman, Hillary has almost always been desperate to be a passionate participant and at the center of events: familial, generational, experiential, political, historical. Call it ambition, call it the desire to make the world a better place — she has been driven. Rarely has she stepped aside voluntarily into passivity. Introspection, however, has not been her strong suit; faith in the Lord, and in herself, is.

"Three pillars have held her up through one crisis after another in a life creased by personal difficulties and public and private battles: her religious faith; her powerful urge toward both service and its accompanying sense (for good or ill) of self-importance; and a fierce desire for privacy and secrecy. It is the last of these that seems to cast a larger and larger shadow over who she really is...

"Hillary is neither the demon of the right's perception, nor a feminist saint, nor is she particularly emblematic of her time — perhaps more old-fashioned than modern. Hers is a story of strength and vulnerability, a woman's story. She is an intelligent woman endowed with energy, enthusiasm, humor, tempestuousness, inner strength, spontaneity in private, lethal (almost) powers of retribution, real-life lines that come from deep wounds, and the language skills of a sailor (and of a minister), all evidence of her passion — which, down deep, is perhaps her most enduring and even endearing trait....

"Great politicians have always been marked by the consistency of their core beliefs, their strength of character in advocacy, and the self-knowledge that informs bold leadership. Almost always, Hillary has stood for good things. Yet there is often a disconnect between her convictions and words, and her actions. This is where Hillary disappoints. But the jury remains out. She still has time to prove her case, to effectuate those things that make her special, not fear them or camouflage them. We would all be the better for it, because what lies within may have the potential to change the world, if only a little."