Trade unions seem like a handy way for workers to organise, albeit with some exceptions, like say cop unions.

• What place do they have in socialist society? They exist in at least Cuba and China, but Solidarity in Poland enjoyed CIA funding.
• What benefits do they offer workers in these societies that aren't already offered by a socialist state, or do they serve a different role?
• How does one convince people of the benefit of trade unions in spite of their fear of corruption of said unions in non-socialist states?

Again, I could be going about it all wrong but yeah.

Thanks!