The reservoir of good will for Barack Obama is deep in the Democratic Party.

He was the embodiment of a moment when people were invested in the ideas of hope and change, believing that he represented an inexorable evolution of the country toward a more egalitarian tomorrow.

And on Tuesday night he attempted to resurrect that feeling, to make people remember the time and place that the lightning had struck, to make them believe that Kamala Harris was in many ways a continuation of, and a natural heir to, his legacy and mantle.

As the former first lady Michelle Obama said before her husband took the stage, “America, hope is making a comeback.”

Indeed, Obama was still proselytizing a form of rainbow-ism that the Trump years proved is not a natural, inevitable progression for America, but is instead a defense against an endemic part of America.

America is near a fracture, and electing Harris may be the only way to prevent it.

In his speech, Obama quoted Abraham Lincoln’s first inaugural address, in which Lincoln counseled Americans not to let passionate disagreement “break our bonds of affection.” Obama quoted it as if it were about idealized unity.

In fact, Lincoln’s address was an attempt to appease Southern enslavers, an effort that ultimately failed, thrusting the country into the Civil War.

Obama was accidentally prescient here, if anything he does is truly accidental. The situation in the country is just as tenuous now as it was when Lincoln spoke those words, and the opponents of equality and progress are just as strident.

Harris has come into that doom circle not selling Obama-era hope but a close cousin of it: joy. She is directing her campaign to the half of an electorate traumatized by Donald Trump and dreading the possibility of his return.

Harris is selling joy as an antidote to despair. She is selling optimism to Democrats who had fallen so deeply into a depression, and for so long that they could no longer fully appreciate the magnitude of their own sorrow.

Hope is an investment in the future; joy is a payout in the now.

Many of us will never forget what Obama meant to the country, how important and transformative his presidency was, not just in policy but as a radical alteration of the image of power, efficacy and excellence.

But the Obama era existed in a moment in time, and it cannot be recalled at will, no matter how much he and others may wish it so. This is a new day, a new era, a Kamala Harris era, and she was meant for her own moment on her own terms.

In this era, it’s not so much about the audacity of hope as it is about a radical insistence on joy.