Ok rather crude scenario but i think it generates an interesting question...
Hypothetically if one was to look into left wing politics for the first time, one would liikely associate leninists, trotyskyite etc groups as being 'marxists' whereas would associate anarchists with bakunin as if there is some kind of irreconcilable difference between 'marxists' (as identified with the aformentioned groupings) and 'anarchism'. The same hypothetical person, id imagine, would be somewhat surprised when going onto an 'anarchist' forum like this and find that there are infinately more threads about marx than any 'anarchist' thinker. So the question following from that standpoint, what is it about anarchist thought that 'completes' as it were, 'marxian' analysis? Also, what makes the anarchist strand of marxism more attractive than the standard standard bearers of marxist tradition?
I
. I agree with the rest of what you say, though.
. Does anarchism add to Marx as a really existing historical actor (I would say yes, I think the beef between Marx and Bakunin is something more than just a clash of personalities), Marxism as a loose umbrella term?** again I would say yes, there are some pretty duff 'marxisms'*** out there as in, political groups that actively engage in social movements etc, etc), or Marx as a
. I think in terms of history, anarchism has had a lot to say to the socialist movement (some just call this 'marxist'), neither of them have been a 'success', but they are both still relevant.
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have I gone too far? 


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I've often wondered about this as well. I like what Angelus Novus wrote on some other thread: (To paraphrase,) as a strand of socialist thought, anarchism is not very interesting and not exactly known for theoretical breakthroughs (and even much less so since WW2), but parts of it are extremely interesting in terms of historical experience and form of practice of the workers movement (personally, I'd emphasize the importance of the historical IWW, as well as the revolutionary minorities in Spain).
So I don't think anarchism has much to add to Marx (and many dissenting marxists) in terms of analysis (even in the case of the state), except when it comes to organizational forms; and what makes it interesting is primarily the historical experience.