I thought I was done worrying about Vladimir Putin. I left Moscow in 2014 as the departing U.S. ambassador, after Putin spent my two-year stint deploying state-controlled media outlets and their surrogates to propagate disinformation about me. He’d been received tepidly in his campaign to retake the presidency from his ally, Dmitry Medvedev, and he needed an enemy. So his proxies falsely argued that I had been sent by President Barack Obama to fund the opposition and foment revolution; that I hoped Putin would end up like Serbian autocrat Slobodan Milosevic, dislodged and imprisoned; and that I was a pedophile. It was a demoralizing dimension of an otherwise great job, but the White House defended me zealously. (In meetings with both Putin and Medvedev, Obama criticized their treatment of me.) When I returned to my teaching position in 2014, I was relieved to leave it all behind.

But this month, at the Helsinki summit between Presidents Donald Trump and Putin, Putin was after me again, and at first I didn’t understand how sinister his attack was. During his two-hour one-on-one meeting with Trump, Putin made his American counterpart an offer: He would permit U.S. law enforcement officials to witness the Russian interrogation of 12 Russian spies accusedby the United States of interfering in the 2016 campaign, if his own agents could observe the interrogation of a similar number of American intelligence officers who, Russia alleges, committed crimes on Russian soil. In the fantasy Putin spun during the joint news conference, U.S. intelligence officers had helped American-born British citizen Bill Browder launder money out of Russia, which Browder then gave to Hillary Clinton’s presidential campaign. It was a ludicrously false equivalency that linked the documented efforts of Russian hackers to tilt the election to Trump with a host of completely imagined offenses by U.S. government officials. Amazingly, Trump called Putin’s crazy proposal “an incredible offer.”

I was in Helsinki, too, as an analyst for NBC News. My initial reaction was incredulity. First, it was obvious that if Putin — a former KGB officer — could stand next to Trump and lie on world television about Russian noninterference in the election, his military intelligence officers would obviously do the same. Second, Putin’s fabricated story was insulting; of course American intelligence officers had not used their positions to aid someone’s alleged money laundering scheme. The blatant defamation of American officials, as Putin stood next to our president, really angered me. Third, this was classic “whataboutism,” a favorite Putin tactic in which he compares, for instance, the annexation of Crimea with something unrelated, like Kosovar independence. In Helsinki, however, Putin simply invented the comparable crime.

I didn’t think Trump was malicious to see merit in this cynical, deceitful offer. He has been naive about Putin and his autocratic regime for years; this was another expression of his misunderstanding of Putin’s methods, or so I believed in the moment. (Trump’s praise underscored why he should never have held a tete-a-tete with Putin. If he could get played on such an obvious no-no – handing over our intelligence officers to Russian interrogators – what else did he agree to in private?) It was just one more symptom of his gullibility, like his choice, during the presser, to side with Putin and against his own government on the question of 2016 meddling: “President Putin was extremely strong and powerful in his denial today.”

Then, on the flight home, Russian journalists began pinging me, asking for my reaction to a statement from the spokesman for the top Russian prosecutor that implied I was under investigation for violating Russian law! “We’re ready to send another request to the US authorities to grant us permission to question these very employees of the US intelligence agencies, as well as a number of other US government officials and businessmen, in order to charge them for the crimes committed by Browder,” it said, citing my name as one of those government officials.

Here we go again, I thought. As the first U.S. envoy to Moscow to be banned from traveling to Russia since George Kennan, I thought my days of dealing directly with Putin’s regime were over. Yet, here it was spewing yet another crazy story about me, only now ratcheting up the intimidation by accusing me of a crime. Putin has silenced many domestic critics with disinformation and false legal charges. Now, amazingly, he was reaching out to muzzle an American professor, thousands of miles away in California.

On the long plane ride home, my incredulity over Putin’s chutzpah eventually morphed into anger with Trump. Why had my president — my commander in chief, my fellow American — called Putin’s scheme to defame, scare and threaten me and other critics of Putin “an incredible offer”? An American president cannot establish the dangerous precedent of allowing any foreign government, let alone a hostile power, to interrogate or threaten to indict American officials for work they did while serving in the U.S. government. If this could happen to a former senior White House official and ambassador who had immunity while working abroad, what could happen to ordinary diplomats? Or intelligence officers? Or soldiers? Or aid workers? Surely, I reasoned, Trump’s team would get this cleaned up, on the record, when he returned to American soil.

In their first attempt to correct the record, they failed miserably. A few days after the Helsinki summit, press secretary Sarah Huckabee Sanders said the White House was still considering Putin’s proposal for reciprocal interrogation of alleged criminals.

What? Did she too not grasp the gravity of this error? A flurry of outraged public reaction ensued, punctuated by a very rare bipartisan 98-to-0 vote in the Senate in defense of me and my fellow Americans on Putin’s list. The State Department spokeswoman, Heather Nauert, flatly dismissed Putin’s suggestion as “absurd” — but also made clear that she was not speaking for the White House.

In the third attempt to explain U.S. policy regarding Putin’s offer, Sanders said Trump had rejected the offer but still applauded the “sincerity” of the Russian president’s proposal. I’m not sure what was sincere about accusing me and others of some crazy crime to help the Clinton campaign by conspiring with a British businessman, but I was upset that my president hadn’t made a better effort – full-throated and without any qualification – to defend us. We all served, and some are still serving, our great country with honor. We do not deserve to be threatened by a foreign autocrat. This is not a partisan issue; this is an American issue.

I’m relieved to know that my government will not ask me to be interrogated by Russian law enforcement officials, but I still need my president to defend me and the other Americans from the next possible escalatory step — a warrant for my arrest, followed by the issuance of a Red Notice by Interpol to detain me in a third country and, in the worst of all worlds, extradite me to Russia. The Russian government has a reputation for abusing Interpol procedures for political ends.

In the end, it’s a low-probability event that Putin will order his government to indict a former U.S. ambassador for an invented crime. But I want it to be a zero-probability event, as does my family. And I want my government to help.

That’s because low-probability events occur increasingly often where Russia is concerned: the illegitimate arrest and murder, in prison, of Sergei Magnitsky; the annexation of Crimea; the downing of Malaysia Airlines Flight 17, a civilian jet flying over Ukraine, that killed nearly 300 people; the intervention in Syria to prop up a murderous dictator; the assassination of a former first deputy prime minister, Boris Nemtsov, just steps away from the Kremlin; the audacious Russian attack on American sovereignty during the 2016 presidential election; the poisoning of the Skripals with a Soviet chemical weapon on British territory; and the spinning of a conspiratorial tale at a major summit about how a British businessman colluded with U.S. intelligence officers, congressional staffers and former State Department officials (from both the George W. Bush and Obama administrations) to steal Russian cash and help the Clinton campaign.

Putin already has done real damage to my professional and personal life. I once was a scholar of Russian politics, but now I can’t travel to that country to conduct research, at least in the Putin era. Even if Russia removed me from its travel ban list, I would not risk going back now with the threat of arrest lingering. Since 1983, I have traveled and lived in the U.S.S.R. and Russia constantly, residing roughly half a dozen years there. I have hundreds of close Russian friends, thousands of acquaintances, and deep interests in Russian culture and history. That chapter of my life, spanning more than three decades, is now over.

I hope Trump, Secretary of State Mike Pompeo, Attorney General Jeff Sessions and national security adviser John Bolton don’t give Putin another victory in his personal vendetta against me by allowing him to throw around false charges, bogus indictments and improper Red Notices issued in third countries. I hope they stand up — clearly, emphatically and publicly — for all Americans serving their country abroad and tell their Russian counterparts that charging (let alone dispatching Interpol to seize) former U.S. officials with fantastical crimes would be met with outrage, new sanctions and reciprocal measures.

That much, at least, should be easy. If the Trump administration does not act, then Congress should adopt new sanctions and other coercive moves to deter Russia from threatening U.S. government officials with detention. If the United States fails to protect its own citizens, it will send a message of weakness and permissibility to Moscow (and everywhere else). That signal will not help Trump obtain his objectives in negotiations with Russia (or anyone else). Putin, and the world, will be watching.

Michael McFaul is the director of the Freeman Spogli Institute for International Studies and a Hoover fellow at Stanford University, was the U.S. ambassador to Russia from 2012 to 2014. He is the author, most recently, of “From Cold War to Hot Peace.”

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