I doubt that you would mean to say that kind of partsanship is THE biggest obstacle... but it comes off that way, despite the last paragraph.
Just re-read my post, please, please.
I said partisan allegiance is NO KIND OF PROBLEM in uniting people in real-life movements, in my experience.
I said it doesn't even ARISE FOR DISCUSSION in those movements.
I said it's only an issue for PEOPLE WHO ARE DISCONNECTED FROM REAL LIFE STRUGGLES. I described the number of such people as a HANDFUL OF INDIVIDUALS.
And if I didn't say all that clearly enough - hopefully the above is clear.
But the diversion of real movements into illusions that the only way to achieve real change is through the ballot box... yes, that's a problem - not the only one by any means - but, as I said, "one of the big ones".