In political jargon a “useful idiot” is a term for someone who disseminate propaganda for causes whose goals they are not fully aware of, and who are used cynically by the leaders of that cause. The term is attributed to Vladimir Lenin, but it’s unclear if he actually used the term.
History is littered with left-causes which have been co-opted by authoritarians. Britain’s most famous example are possibly those of George Orwell’s experiences in the Spanish Civil War when Stalinists purged the anarchists in the middle of the war against Franco, as well as famous writers and intellectuals like Doris Lessing and HG Wells.
Sweden’s left-wing party Vänsterpartiet still suffer from their association with the former East Germany, where the party leader Lars Werner spent a lot of time being plied with Vodka in the Saunas of the country’s embassy.
For people on the left to actually welcome outlets like RT.com and Sputnik News as some kind of alternative media is foolish and naive. Western media has its problems, but unlike the Russian equivalents they are not sharply collared to work with the security services in order to further propaganda. Particularly propaganda for a xenophobic, homophobic, anti-Semitic, cleptocratic form of Russian Chauvinism.
Left-wingers certainly earn the name if they engage with and participate in outlets which propagate the policies of Vladimir Putin. One does well to remember that Putin was a Lieutenant Colonel in the KGB for 16 years, and that exploiting the naivety of Westerners about the nature of the Soviet Union was a part of his brief.
It is one thing to complain about bias in the media, and Western media certainly deserve criticism sometimes. However, there’s never a case for following the dictum “the enemy of my enemy is my friend”. Often the enemy of an enemy is just as terrible as the enemy. And that’s the case with both RT and Sputnik. Left-wingers do well to stay away from both.