As voters in 14 states from Maine to California went to the polls on Super Tuesday, officials from four national security agencies huddled in a nondescript office building just across the Potomac River from Washington to monitor the presidential primaries for any signs of foreign interference. Over the course of the day, say two intelligence officials involved in the exercise, the four agencies connected to state and local election officials via a text messaging platform to allow communication in case poll workers saw issues at voting stations, or federal officials got word of efforts to meddle from abroad.

The exercise, which included the Department of Homeland Security, the FBI, the National Security Agency, and the U.S. Cyber Command, found no signs of direct foreign meddling, the two intelligence officials say. Against the backdrop of continuing propaganda and disinformation campaigns, however, it showed a mixed picture of U.S. efforts to counter foreign interference in U.S. voting this year. Both officials spoke on the condition of anonymity because they are not authorized to comment publicly on the activities they described.

Overall, outside experts say, the U.S. is better prepared to detect and counter foreign election meddling than it was four years ago. “We’re light years ahead of where we were in February 2016,” says David Salvo, the deputy director of the Alliance for Securing Democracy at the German Marshall Fund, which tracks foreign election interference. And contrary to popular belief, Salvo says, President Donald Trump has helped, creating in 2018 the Cybersecurity and Infrastructure Security Agency (CISA) within the Department of Homeland Security, and supporting and funding federal training for state and local officials by the FBI, DHS and others. “President Trump has taken many more steps to secure the elections than people realize,” Salvo says.

Still, say Salvo and other cybersecurity experts in the government and the private sector, U.S. elections remain vulnerable to foreign interference. Congress was so slow to pass election security funding that many states haven’t been able to use it yet. Some states still don’t have paper backup ballots or required audits. And there is no common understanding across online platforms such as Twitter and Facebook about how to deal with foreign disinformation and propaganda.

The foremost threat of direct meddling in the election outcomes, say experts inside and out of government, remains Russia. But for now, Moscow appears focused on more indirect methods of influence, the officials say, including general propaganda and disinformation. Russia has advanced beyond the relatively rudimentary efforts it deployed in those fields in the 2016 election, the officials say. It has been developing a more sophisticated understanding of America’s social, economic, and political divisions to microtarget its efforts to exploit them and discredit the entire electoral process, says Salvo. “They know us really, really well,” he says.

U.S. officials agree. “The Russians are targeting their propaganda the same way Amazon and others target advertising,” says a third U.S. intelligence official, also speaking on the condition of anonymity. “They’re looking at zip codes, congressional districts, demographics, ethnicity, and other indicators and moving quickly to pounce on anything in the news they can use to amplify grievances.”

The Russians pounced on the chaos in reporting the results of Iowa’s precinct caucuses by calling the delays an effort to deny Vermont Independent Sen. Bernie Sanders a clear win and falsely suggesting some of his rivals had some ties to the computer application that failed, according to a recent report by the Marshall Fund’s Alliance for Securing Democracy.

One favorite Russian theme is that “the Democratic Establishment” and the mainstream media are trying to prevent Sanders from winning the Democratic nomination, according to the report. For example, just before the South Carolina primary, Russia’s government-controlled Sputnik News ran a story under the headline, “Democratic Megadonor Urges Party Leaders to Back Candidate to Block Sanders’ Nomination”.

Although the intelligence so far is inconclusive, one of the officials said, after former Vice President Joe Biden rebounded in South Carolina, “it looks like the Russians went back to what they did in 2016—digging up or making up dirt on Biden for his son’s business dealings in Ukraine.”

Sanders is mentioned more than twice as many times as any other Democratic candidate in the first 200 words of Russian articles from Feb. 22 to 28, according to an analysis by the Alliance for Securing Democracy. But it’s a mistake to think the Kremlin is backing his candidacy, or Trump’s for that matter, says Zack Cooper, co-director of the Alliance. “Putin’s underlying goal is to dampen democracy’s appeal to would-be activists within Russia. It’s also to keep us divided and distracted, making it less likely that we would play a more forward-leaning global role that could be detrimental to Russia’s foreign policy interests. In other words, to make us look weak and to actually weaken us.”

“It doesn’t have to be either/or,” says a former CIA officer and White House official who requested anonymity. “If you’re Putin, why not help Sanders? If a Democrat is going to win in November, you’d probably want it to be him owing to his rather isolationist tendencies. And if you want Trump to win—as the Russians almost certainly do—the conventional wisdom is that Sanders would be the weakest opponent the Dems could muster.”

Complicating the issue, Russia is no longer alone in posing these threats, says Salvo. “The Iranian regime is starting to mimic these tactics,” he says. “They’re taking pages out of the Russian playbook.”

In a statement on Monday, the heads of the four agencies warned “foreign actors” that they could face “sharp consequences” for such efforts, without saying what those consequences might include. In the wake of the 2016 Russian election meddling, the U.S. expelled suspected Russian spies, shuttered two Russian facilities in the U.S. and imposed sanctions on companies and individuals associated with Russian activities abroad.

Two U.S. intelligence officials tell TIME the U.S. Cyber Command, part of the Defense Department, was prepared to take offensive action against foreign hackers who tried to intervene in the elections. That could include shutting down foreign operations as they attempt to meddle. In 2018, Cyber Command launched operations against hackers in the run-up to midterm elections.

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