Editor's Note: Eric H. Holder Jr. was the US attorney general from 2009 to 2015. The views expressed in this commentary are his own. View more opinion articles on CNN.
(CNN) - As 10 Democratic contenders take the stage this Thursday night for the next presidential debate, the most important question they'll face is one the moderators probably won't ask.
Their judgment, experience, and positions on key issues are all important for primary voters to consider—and of course defeating Donald Trump and ending his corrupt administration must remain a top priority. But with polls suggesting, at this early stage, that victory could potentially be within reach for virtually any candidate, when I tune in this Thursday, the most important question on my mind will be which Democrat is the most effective advocate not only for her or himself, but for the record, vision and values of the Democratic Party of today and years past.
In other words: which candidate deserves to be not just our nominee in 2020, but our leader for the next generation?
The most recent round of debates, in July, was filled with missed opportunities to answer this question. Many candidates spent too much time in the weeds, developing "gotcha" moments or straining to draw personal or policy distinctions—at once testing viewers' patience and missing the forest for the trees.
This is not to suggest that the many differences between candidates are insignificant. But voters don't tune in to prime-time debates to watch hours of wonkish hair-splitting. They—we—are hungry for someone to present an affirmative vision for America, post-Trump.
Which is why Democrats, having been granted three hours of national airtime to show the American people what we stand for, can ill-afford to squander this opportunity on minor disagreements. Airing significant, substantive contrasts is, as always, important—but candidates would do well to remember that the contrast that matters most is the one between Democrats' hopeful, inclusive agenda and the divisive, self-destructive, special interest-driven record of the Trump administration.
Unfortunately, there were moments during the last round of debates that played into Republican attempts to muddy this crystal-clear distinction. Invited to compare President Trump's appalling deportation and family separation policy to deportations under President Obama, in whose administration I served as US Attorney General, more than one Democrat took the bait.
Any critique of our most recent President is, of course, fair game—even if (as I tweeted that night, and as my friend Denis McDonough argued in the Washington Post) it doesn't amount to a sound political strategy or a good use of precious speaking time during a debate. The trouble is that—in failing to firmly reject the premise that Obama's policy was in any way comparable to Trump's—our own candidates helped perpetuate the Republican lie that the Obama administration's good-faith actions under a broken immigration system were somehow equivalent to Trump's policy of intentional cruelty: deterring asylum-seekers by breaking their families apart and keeping children in cages.
If Democrats are to have any hope of winning next fall, we need our presidential contenders to do better. Falling short of our policy ideals is not the same as affirmatively and deliberately harming innocent families, and it's counterproductive—even offensive—to suggest otherwise.
What matters in 2020 is not what a given candidate might've done in Obama's shoes nearly a decade ago, given the benefit of hindsight and without any of the political, policy, and legal constraints Obama actually faced. What matters is whether we can count on our nominee to effectively lead the nation today—and manage an executive branch Trump has nearly reduced to ruins—by building upon, rather than denigrating, the record of achievement established by Obama and other Democratic presidents as far back as FDR.
It's a record in which every Democrat should take pride—and upon which our next standard-bearer must campaign, rather than attack by accepting as real Republican talking points.
After all, ours is the party of Social Security, Medicare, Medicaid and the Affordable Care Act—all of which we've fought hard to protect against Republican efforts to tear down over decades.
Ours is the party that helped rally the world to fight climate change—and that values, secures, and strengthens the kinds of international agreements that these new Republicans shred for purely political and corrupt economic reasons, sowing global instability, rattling our most important alliances and emboldening dictators in the process.
Where Republicans stand for voter suppression and gerrymandering that allows politicians to pick their voters (rather than the other way around), Democrats support voting rights and fair elections. Where Republicans support minor changes to the criminal justice system, Democrats support the broad changes that are required to make the system more just.
We fight for racial and religious equality, for civil rights and LGBT rights, and for common sense immigration policy and gun safety laws. And we'd never tolerate racist rhetoric from a president who traffics in xenophobia and draws enthusiastic praise from avowed white supremacists and Nazis—let alone enact policies that discriminate against immigrants, Muslims, LGBTQ Americans, women and so many others.
Advocating hard for the broader Democratic agenda that is rooted in our history as a party should be our candidates' major focus on Thursday night.
During the debate and as the 2020 race continues, I invite my fellow primary voters to seek out and support the candidate who's proudest to run on our party's extraordinary record, who lays out the most compelling vision for building upon it, and who's willing to fight for the progressive, inclusive values that underlie so much of the history that we've made together.