Emerson T. Brooking is a resident fellow at the Digital Forensic Research Lab of the Atlantic Council. He is co-author of “LikeWar: The Weaponization of Social Media.”

Last week, Facebook revealed details of a new Russian influence operation targeting the 2020 U.S. election. Sticking to the playbook they used in the 2016 presidential election, Russian operatives infiltrated both sides of contentious political debates, seeking to widen the fissures in American society. The operation focused on Instagram and reached roughly 147,000 U.S.-based Instagram users. The efforts concentrated on the swing state of Florida.

Yet unlike 2016, when most Russian activity occurred during the general election, this operation took place amid a heated Democratic primary. This marks a troubling development. Despite all the study of state-sponsored disinformation over the past three years, we still have little knowledge of how a foreign influence operation might affect a crowded and contentious intra-party contest. There is a real danger that Russian interference — and the suspicion of Russian interference — will hang over the primary like a storm cloud, poisoning debate and infuriating progressive activists. It will also offer political ammunition to President Trump, who will use all the instruments of government to exploit it.

This new Russian activity seems destined to reopen old wounds. According to a report from the the data analysis firm Graphika, Russian operatives created fake African American news outlets to tarnish former vice president Joe Biden while boosting the candidacy of Sen. Bernie Sanders (I-Vt.). This is an eerie reflection of Kremlin mischief-making in 2016, when its operatives adopted the same techniques in order to encourage the defection of Sanders primary voters from Hillary Clinton, then the Democratic nominee.

Although the strategy did not work (fewer Sanders voters defected from Clinton than Clinton voters defected from Barack Obama in 2008), it left a bitter legacy. In the aftermath of Clinton’s defeat, some supporters suggested that Sanders had effectively derailed the election — and that his grass-roots popularity stemmed from the efforts of Russian trolls in St. Petersburg. For these former supporters of Clinton, many now supporters of Biden, it might feel as if history is repeating itself.

News of this latest Russian influence effort arrives at a moment when establishment Democrats are already primed to see Russia’s hand in every challenge or political setback. Just last week, Clinton suggested that Rep. Tulsi Gabbard (D-Hawaii) — another Democratic presidential candidate who has been the target of positive Russian propaganda — was being “groomed” to run as a spoiler on a third-party ticket. As Sanders rose to Gabbard’s defense (“It is outrageous for anyone to suggest that Tulsi is a foreign asset”), an online chorus accused him of being a Russian asset as well.

This infighting threatens to overshadow the substantive policy debates that are now unfolding within the Democratic Party. Should the Democratic establishment continue to lose ground relative to the ascendant progressive wing, some will be tempted to blame these losses on the meddling of a foreign power instead of the actions of a popular movement. This will alienate progressive candidates and infuriate the progressive base, making it harder to unite for the 2020 general election. Ironically, such intractable debate over the nature and purpose of Russian influence operations is exactly what Russia wants.

All the while, Trump will watch this conflict like a vulture. In contrast to 2016, he is safe in his nomination and sits atop a campaign war chest that dwarfs all competitors. The president has already demonstrated his willingness to use federal agencies to his personal political ends. Trump has also taken every opportunity to obfuscate the issue of Russian interference, seeking to minimize the disinformation campaign that helped bring him to power. If he sees an opportunity to attack the Democratic Party by using “Russia” as a cudgel, he will do so.

It is easy to imagine a future in which Russia launches increasingly transparent influence activities on behalf of candidates such as Sanders or Sen. Elizabeth Warren (D-Mass.). Contrary to the aims of a traditional intelligence operation, discovery and attribution will be the point, derailing the primary with news of yet another Russian disinformation campaign and driving a wedge between the Democratic factions. As media coverage mounts, Trump will feel justified in launching an investigation, ensuring that his political rivals are not “profiting” from the efforts of a foreign power (and possibly distracting from other operations working to his own benefit.) All the old narratives will be turned on their head. It will be Democrats, not Republicans, who suffer Russia as a campaign issue, no matter how loudly they disavow the operations conducted in their name.

Although foreign interference remains the gravest threat to the future of free and fair U.S. elections, the issue of foreign interference represents a counterproductive and potentially dangerous one for the Democratic primary. Democratic campaigns must give each other the benefit of the doubt. If they use the existence of foreign influence operations to score cheap political points against fellow Democrats, it will be the party — and the country — that ultimately pays the price.

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