I don't think militant communism would help those countries much. By Marx's own words, they lack the developments that would, in theory, allow a socialist system to work in the first place. In the end they would probably go down a Mugabe-style road.
I think these things are true of certain Marxists, but not Marx himself. He was well aware of (and had plenty of dialogue with) a whole host of people and movements that attempted to address the abuses of capitalism without resorting to violent revolution. In his writings, he frequently addresses the likes of the Saint-Simonians, Owenites, Chartists etc. In fact, the latter example there is particularly significant, since Marx himself said that unlike in Europe, Britain's suffrage laws would allow for the working-classes to achieve real political representation through a democratic system. Marx wasn't the blinkered radical many of hs followers became.
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