Seeing the conversations around this topic in the post Most Western Parties Are Ossified and Failures I thought some folks might find value in this organizing guide created by USU. It draws from numerous articles they’ve written about organizing ML orgs from the ground up.
never succeeded therefore don’t try
But they have succeeded!
Okay, what have they achieved?
The New Deal, the presence of labor unions, and Social Security and Medicare/Medicaid, including the civil rights revolution of the 1960s/70s.
Firstly you are conflating union action with Socialist parties, and much of these things you’ve mentioned only came to pass because during the cold war, the Capitalists felt the need to hand out concessions regardless because of the presence of the Eastern Bloc as an alternative economic model. As soon as the Soviet union fell, almost every single thing you’ve mentioned has been gutted in the west. Goes to show how effective the socialists were in the west when all their success could have been rolled back the moment the external competition was eliminated. Compare this to AES, like Cuba, China etc. and you can see what the difference is between actual success in a socialist movement, and what’s been done in 100 years in the west.