The CIA pulled its top agent in Russia out of the country in 2017 because the agency feared authorities there might uncover the source at any moment. CNN and the New York Times say those fears stemmed at least in part from President Trump’s loose lips. So who was our man (or woman) in Moscow and why did the since retired agent turn up at the center of yet another political feud over the 2016 election?

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Who can it be? The New York Times reported late Monday that the source in the CNN story was the same source that the Times had previously hinted at—a Russian official who wasn’t among Putin’s intimates but was close enough to his decision-making to offer the U.S. a rare glimpse into what the most senior levels of the Kremlin were thinking. After the source had served as a U.S. agent for decades, the CIA offered to extract them. The informant, not wanting to flee home, initially refused, leading to fears that the informant might have been a double agent.