In 2020 Democratic primary, we'll face reckoning over Russia. Will we let Putin divide us? Russia will almost certainly interfere in the 2020 election, but not as you might expect. The Democratic primary could be ripe for Russian tampering.

Robby Mook | Opinion contributor

Show Caption Hide Caption US officials raise alarm about election security Top U.S. intelligence and homeland security officials are raising alarms about potential efforts to influence the 2018 and 2020 elections. (Aug. 2)

The revelation last week that foreign agents (likely Russian) were running a Facebook campaign to influence the midterm elections cemented what we already suspected: Foreign influence operations are now a permanent part of election campaigns, like super PACs and voter suppression laws.

For Democrats, it should be a warning that we have a tough reckoning ahead — and not in the way you might think.

The narrative of Russian interventions in the 2016 general election is politically convenient. President Vladimir Putin, a murderous, villainous despot, knew he could manipulate President Donald Trump, so he decided to help him win. But what about the fact that Putin also helped Sen. Bernie Sanders? That’s more awkward. I don’t believe that Bernie asked or wanted the Russians to try to bolster his chances, but that’s the point. The Russians will do what’s best for Trump without regard for what any of us want or expect.

Russia wants Democrats divided

The Russians know there’s no better way to help Trump win re-election than divide Democrats and disrupt our primary. They will choose sides. They will seek to inflate divisions on race, gender and geography. They will trump up "scandals" and suspicions of "rigging." They will infiltrate conversations in our Facebook groups and Twitter threads, and pollute our feeds with manufactured content. There’s no question it will happen. The question is: What will we do about it?

To be clear, I look forward to a sprawling, highly competitive presidential primary next year. A wide variety of choices and a spirited debate about the direction of our country is healthy and will produce the best candidate possible. We should welcome the differences in opinion and passions it will evoke. We just don’t want the Russians manufacturing ways to make it unnecessarily nasty or divisive.

Every Democrat considering a run for president needs to carefully consider where she or he will stand when Russian rumor mongering seeks to divide Democrats. If Russia attacks your opponent or promotes you, will you let it slide? Or will you speak out? Will you commit to ignoring stolen and leaked material? Will you be willing to call on supporters to shut down Facebook groups infected with agents posing as supporters?

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What’s most frightening is how ripe an opportunity Putin and Trump have to pursue the age-old strategy of turning your enemy’s greatest strength into a weakness. In our case, this is our diversity. The Democratic primary electorate is vastly more diverse than the Republican one:

►In 2016, nearly 60 percent of Democratic primary voters were women.

►In many states, including Georgia, Alabama, South Carolina, Texas, Mississippi and Maryland, over half the primary electorate is people of color.

►Young people are identifying as Democrats by almost 2-1.

This is our strength. This coalition has won us elections when we are focused and united. But undoubtedly the Russians will see the Democratic primary as a perfect opportunity to get us focused on our internal differences, not the chasm between us and Donald Trump.

The precedent on this is clear. A study released by the House Intelligence Committee of more than 3,000 Facebook ads purchased by the Russian Internet Research Agency showed that more than half focused explicitly on race.

Trump welcomes a Russian distraction

Russia and Trump will also make every effort to undermine the nominating process itself. Get ready to hear them call the process "rigged" and single out some candidates as victims of an amorphous "establishment," whether it’s the news media, the Democratic National Committee or the nominating rules. For some candidates, feeding into these perceptions will be incredibly appealing. Assuming there’s a big field, it’s almost certain no candidate will go into the Democratic National Convention with a majority of delegates. Rumors of “rigging” or unfair treatment, amplified by Russia and legitimized by candidates, could rob us of precious time to heal and mobilize if we don’t unify behind our nominee in time.

Nothing could be better for Trump. He remains popular because he has quashed a real debate about his long list of broken promises: How his corrupt administration has made Washington more swampy, not less. How he has made health insurance much more expensive and actively fought to allow insurance companies to drop coverage for people with pre-existing conditions. How he gave massive tax cuts to billionaires and corporations, while wages for working people remain stagnant.

He will lose if the election is a referendum on his leadership, so he — and his de facto Russian-sponsored super PAC — will do everything they can to get us fighting with each other. They want Democrats shouting about the nominating process, not how Trump is endangering people’s lives and driving down wages.

As we continue to learn more about what the Russians did two years ago, we shouldn’t miss the opportunity it provides us to have a hard conversation about how we Democrats can stand unified in the face of foreign influence. It’s a chance to set an example for the world, a chance to defeat Putin. But we can’t wait until it’s too late, lest our primary becomes a contest about our differences, not our values.

Robby Mook, a fellow at the Harvard Kennedy School's Belfer Center for Science and International Affairs, managed Hillary Clinton’s 2016 presidential campaign. Follow him on Twitter: @robbymook.