As a new Russia-related scandal sweeps Washington, it's impossible not to recall President Vladimir Putin's efforts in 2012 to make meetings with the U.S. ambassador to Moscow toxic. As Trump's opponents seek to inflict maximum damage for Attorney General Jeff Sessions' false denial about a meeting with a Russian envoy, they should understand where these games lead.

For Putin, whose suspicion of foreign diplomats was nurtured during his years as an intelligence officer, it all began in 2007.

"Unfortunately, there are still those in our country who scavenge at foreign embassies, counting on the support of foreign foundations and governments rather than the support of their own people," Putin famously told a rally of his supporters in 2007. The word Putin used for "scavenge" — shakalit — is derived from the Russian for "jackal."

Still, Putin didn't really make it difficult for Russians to seek out foreigners for financial support or to attend embassy receptions to network until the beginning of his third presidential term in 2012. After mass protests against a rigged parliamentary election in 2011, Putin became convinced that the U.S. had just attempted regime change in Russia, so he moved against what he saw as pernicious U.S. influence.

It was in 2012 that Russia booted out the U.S. Agency for International Development for meddling in Russia's domestic affairs through "attempts to influence political processes through its grants," according to the Russian Foreign Ministry. A sustained campaign began against foreign-funded nonprofit organizations culminated in the passage of Russia's infamous law on nongovernmental organizations, which obliged groups that conducted "political activities" to register as "foreign agents" if they received any overseas grants.

It was also in 2012 that Michael McFaul, newly arrived in Moscow as U.S. ambassador, held his first official meeting after visiting the foreign ministry to present credentials. The meeting was with well-known anti-Putin opposition figures, including Boris Nemtsov, who would later be murdered not far from the Kremlin. The 2011 protests came up during the discussion.

McFaul, a Stanford academic who had spent years in Moscow, likely didn't attach much practical significance to the symbolic meeting. Putin's people did. Throughout that year, reporters from NTV, a state-owned, pro-Kremlin TV channel, hounded him every time he tried to meet with an opposition figure — or, indeed, go almost anywhere, though they never said how they knew his schedule. McFaul complained about the harassment, as did the U.S. government.

The Kremlin's signal was clear: Even meeting with McFaul was tantamount to flirting with the enemy. This led to a poignant Twitter exchange between McFaul and Alexei Navalny, who is still the most popular Putin opponent in Russia.

"We should meet someday," McFaul tweeted to Navalny in English. "Odd that everyone thinks we hang out every night when in fact we have never since I came to Moscow."

Navalny responded in Russian: "OK, let's meet at Komsomolskaya subway station, in the middle of the platform. I'll carry a copy of the Ogonyok magazine, and I'll recognize you by the American flag you'll carry."

"I get it," McFaul tweeted back.

Just as Putin did in 2012, Trump's critics in Congress — and in the media — are turning Russian representatives in the U.S. into pariahs. And without evidence of wrongdoing so far.

Even former national security adviser Michael Flynn, a Russia dove, apparently didn't talk about anything reprehensible with Russian envoy to Washington Sergey Kislyak. Sessions, a senator at the time and a Russia hawk, met with lots of other ambassadors, too. The most obvious problem with meeting Kislyak — in Sessions' Senate office no less — is that he is perceived as toxic in Washington as Putin's representative.

How far can the stigma stretch? Do businesses have to worry that seeking Russian funding for projects will magically transform them into Russian agents?

Will any person who could be described as a Putin regime associate automatically become suspect? Should they all be surveilled, with leaked transcripts of contacts with Americans spilling out into the media at politically opportune times?

The smarter alternative is to stay away from Russian ambassadors. It's their job to have lots of polite and often pointless meetings. If Russia did influence the U.S. election, it can't have been through Kislyak — he was too visible, and his communications were clearly subject to intelligence monitoring. He was as guilty of attempting regime change in the U.S. as McFaul was of trying to have Putin overthrown.

A witch hunt involving everyone Kislyak met in the Trump camp is not a good way to show U.S. moral superiority to the Putin regime.

Leonid Bershidsky was the founding editor of the Russian business daily Vedomosti and founded the opinion website Slon.ru.