The sudden, jolting line in Obama's second inaugural address came two-thirds of the way into the speech, when the President declared " ... that all of us are created equal -- is the star that guides us still; just as it guided our forebears through Seneca Falls, and Selma, and Stonewall."
With that sentence, Obama transitioned from what began as a rather sleepy, conventional speech into a soaring declaration of our country's progressive values and the historic journey toward a more just society that includes women's rights, racial equality, gay rights, and immigrant rights -- the values that inspired the nation and won the 2012 Presidential election.
"Our journey is not complete until our wives, our mothers, and daughters can earn a living equal to their efforts," Obama declared.
"Our journey is not complete until our gay brothers and sisters are treated like anyone else under the law."
"Our journey is not complete until no citizen is forced to wait for hours to exercise the right to vote."
"Our journey is not complete until we find a better way to welcome the striving, hopeful immigrants who still see America as a land of opportunity; until bright young students and engineers are enlisted in our workforce rather than expelled from our country."
By connecting the civil-rights struggles of women, black people, gays and lesbians, and immigrants, Obama made a powerful declaration about the central place in history of these progressive movements, and about our country's progressive future.
It was a fitting message for Martin Luther King Day.
And it was a kick in the butt to Republicans.
As Paul Ryan sat listening, Obama delivered a strong rebuke to the Ayn Radian theories that drove the Ryan/Romney campaign about society's "takers" and "makers":
"The commitments we make to each other -- through Medicare, and Medicaid, and Social Security -- these things do not sap our initiative; they strengthen us. They do not make us a nation of takers; they free us to take the risks that make this country great."
Yes, there was a note of caution on the deficit that could mean the President is still open to regressive Republican cuts that could stall economic recovery: "We must make the hard choices to reduce the cost of health care and the size of our deficit."
But, very quickly, he added a defense of the New Deal programs that protect the poor and elderly from disaster -- through government spending:
"But we reject the belief that America must choose between caring for the generation that built this country and investing in the generation that will build its future. For we remember the lessons of our past, when twilight years were spent in poverty, and parents of a child with a disability had nowhere to turn."
The progressive tone of the last third of Obama's speech was so unexpectedly rousing, it jolted the crowd, and listeners of all political persuasions from coast to coast.
There was the strong statement about the threat of climate change -- that America must lead the transition to renewable energy, because "failure to do so would betray our children and future generations."
There was the hopeful statement that "enduring security and lasting peace do not require perpetual war," and the promise (though vague) to end a decade of war.
Instead of a pean to bipartisanship and sensible, middle-of-the-road governance, we got the fiery Obama of the closing days of his last campaign.
He denounced our nation's scandalous inequality: " our country cannot succeed when a shrinking few do very well and a growing many barely make it."
He offered a poignant vision of a better possibility: "We are true to our creed when a little girl born into the bleakest poverty knows that she has the same chance to succeed as anybody else."
We are a long way from realizing that vision.
But the bully pulpit counts for something.
And Obama used it well.
If you liked this article by Ruth Conniff, the political editor of The Progressive, check out her story "Bernie Sanders Urges Obama: Don't Cut Social Programs".
Follow Ruth Conniff @rconniff on Twitter.