Indeed. That's a vexing habit of certain factions of the right. But France seems a country where this faction is dominant within the left. Its Melenchon who's the big left wing challenger while Hollande's old party's been on death's doors for years. And while I certainly don't trust Corbyn he at least got ousted by the British left, albeit for the pretty damning reason of them just wanting to reign as Tories in red.
Usually the pro Russian left wing parties are either powerless fringe parties or freaks, but in France the situation is different.
Because France has nuclear weapons and a nuclear triad. The Germans don't, the Polish don't, and your country doesn't. I suspect France doesn't fear a Russian invasion, but they should fear Russia for other reasons, like hacking/cyberwarfare, overseas targeting of EU, and or French nationals.
The next candidate in the US to win the presidency had better be someone who is serious about Russia, who, like China has viruses in our electric grid, and the EUs as well.
My choice is Sen. Mark Kelly.