A spy from the former communist superpower, the Soviet Union, congratulated socialist Bernie Sanders in March 1983 for winning re-election as mayor of Burlington, Vermont, and for meeting with him in Sanders’ office.

“The documents from the Sanders archives include a letter from Soviet Embassy First Secretary Vadim Kuznetsov in March 1983, congratulating Sanders on his reelection as mayor and thanking Sanders for receiving him in Sanders’s office,” The Washington Post reported on Monday. “Kuznetsov had been in Burlington to attend a conference on nuclear disarmament at the University of Vermont a few days earlier. Neither Sanders nor conference organizers appear to have read a 1976 Time magazine article that identified Kuznetsov as a member of a ‘Soviet intelligence squad’ posing as diplomats to infiltrate U.S. politics.”

The TIME Magazine article that the Post linked to stated: “Posing as diplomats, embassy officials and newsmen, Soviet intelligence agents have been conducting a determined effort to get classified information on Capitol Hill by bribing or compromising staff members in key positions. TIME has learned that in more than a dozen cases in the last decade or so the FBI has stepped in to ‘control’ the relationship, fearing a staffer might begin giving out restricted data.”

The letter that Kuznetsov sent Sanders stated:

Dear Mr. Sanders, Please accept my sincere congratulations on your re-election to the post of Mayor of Burlington. I have been following with a great interest the final stage of this mayoral race which attracted a lot of coverage by the national news media. Thank you for receiving me in your office on February 3. With best wishes, Vadim Kuznetsov

Democrat strategist Zac Petkanas posted a copy of the letter and tweeted: “For the love of all that’s holy. The piece links to the actual letter a Soviet official sent Bernie Sanders congratulating him on getting elected. Can you IMAGINE what Trump would do with this?”

Hoover Institution research fellow Paul R. Gregory, who has a PhD in economics from Harvard, explained in an article last year that Sanders was a socialist because there was little to no difference between what socialists believes and what Sanders believes as a self-described “Democratic Socialist.”

Gregory wrote:

Sanders has spent a long political career obfuscating his true political beliefs. The media rarely pushes back on his standard platitudes, such as “we must create an economy that works for all, not just the very wealthy.” His two-minute video, promising to explain his brand of socialism, leaves the viewer clueless, probably deliberately. Sanders insists that he is not a “socialist” but a “Democratic Socialist,” as if the difference is self-explanatory. When pressed further about his Democratic Socialism, he resorts to filibustering about the Scandinavian-like paradise of free medicine and education, guaranteed jobs, livable wages, and other free things he intends to introduce when elected. He does not bother to note that the Nordic states rank among the most free-enterprise economies of the globe.

Gregory noted that Sanders is “fully on board with the [Democratic Socialists of America (DSA)] narratives of capitalist exploitation and the need to organize” and that there is no distance between what Sanders believes and what DSA promotes.

Gregory notes that according to official DSA literature, Democratic Socialists believe:

First, Democratic Socialism wants more than an expansive welfare state. Second, capitalism is a zero-sum game in which the rich get richer by making the poor and working class worse off. Third, the poor, working class, and other underdogs can overturn the capitalist order only if they are organized. Fourth and most important, capital must be publicly owned because there is no real democracy with private ownership of capital.

Gregory noted that there was essentially no difference between what DSA believes and what socialists believe.

Gregory concluded:

According to CNN files, Sanders advocated in the 1970s the nationalization of most major industries. According to Sanders then: “The oil industry, and the entire energy industry, should be owned by the public and used for the public good – not for additional profits for billionaires.” When asked recently whether his position on nationalization has changed, Sanders pivoted to his “free stuff” filibuster. No answer. What Sanders advocated a half-century back is much less important than his current legislative initiatives. Let’s face it: Sanders’ signature Medicare-for-all, as laid out in his Senate bill, nationalizes all medical care. Private health insurance and employer insurance disappear and private providers must reorganize as non-profits and/or governmental organizations. A massive government bureaucracy determines our medical care – a sort of super VA. If Sanders is prepared to nationalize one fifth of the economy, he should have no qualms about doing the same to his loathed private energy and finance sectors. Marx declared that a socialist revolution would be required to part the capitalists from their capital. Democratic Socialists (DSA and Sanders) see a different path to what they consider true democracy: Organize the poor, the working class, and all other oppressed groups into what James Madison called an “overbearing majority.” Such a coalition would have enough power to transfer capital to the state by “democratic means.”

During an interview on Sunday, President Donald Trump said the following about Sanders: “Well, I think he’s a communist. I mean you know, look. I think of communism when I think of Bernie.”