Under some circumstances, success means one goes to prison instead of being tortured to death.
Under other circumstances success means that one smashes the state and establishes working-class power. (At 74, I clearly won't be around to enjoy that success, if it ever happens.)
Most frequently, for The Left or for those trying to build a left, success means that one learned something that one did not know before. That learning can be as simple as that X has better (or worse) politics than one had expected, or that X is more (or less) dependable than one had assumed.
Less frequently, but offering more satisfaction, one unearths or recruits new comrades who move in different 'circles' than any of those who brought about the action, thus expanding the potential reach of the left as a whole. (E.g., a collective made up of, say, teachers & auto workers, holds a rally and recruits a Walmart employee.) Actual example: SDS at ISU by the spring of 1968 had shrunk to two students, a graduating couple, and me. I and one of the students passed out a little over 100 leaflets for a 'rally' in support of Rap Brown, who had recently been arrested. We recruited one new couple, through whose work the SDS chapter by the spring of 1969 totaled over 25 paid members and was capable of mobilizing demonstrations of near 200.
I have written at some length on the usefulness for left thinking of the metaphor of "punctuated equilibrium" as a perspective on political struggle. One simply cannot, _ever_, predict in advance when a period of equilibrium, when nothing really works very well, will suddenly explode into immense growth. But one works _as though_ such a punctuation were imminent. That is why one has to have such a flexible and undemanding sense of what success is. There will never be any success except as a result of hundreds or thousands of actions that went nowhere.
In any case, one must view an action historically, i.e., one must look at it from the perspective of several years down the road. Some years ago I had a lengthy conversation with ex-CP member (since deceased), then a meber of the RWHq, who told me he had joined the CP when he was 18, in Minneapolis. All one winter he stood (in sub-zero weather) on the same corner every day hawking the Daily Worker. No one ever stopped to buy one. But when warm weather came, everyone who regularly passed that spot remembered the idiot who had stood out there at 30 below hawking a paper, and he formed a local group of some 20 recruits to the CP.
One more thing. If you are not quite willing to make a fool of yourself in public, you aren't really needed by the left as either a theoretician or an organizer.
Within the perspective or set of perspectives I'm trying to roughly map out here, there is no way that the MWM can be other than a success, though I suspect that from the perspective of those who can't stand public embarassment and who live in the present it will be an utter failure. Its actual degree of success won't be clear for half a decade or so. But for those who participate in it (and in the follow-up envisaged by those who called it) it will have kept a movement alive. Presidential election years are usually movement-killers in the U.S.
Carrol