> Yes, they do, they lose members.

And they often use violence or threat of violence to try to stop this - see their reaction to 'scabbing'.

If I say I don't want to work for my company any more they'd either say 'farewell' or even offer me money to stay.

If you don't want to be part of a union or a strike, you better be prepared to be harassed and intimidated.

>And they often use violence or threat of violence to try to stop this - see their reaction to 'scabbing'.

If it's a competition for who has managed the most extreme violence in relation to an industrial dispute in America the prize would go to the manager of a coal mine in west virginia who brought in a private air force to bomb strikers (battle of blair mountain).

I somehow doubt youll find a union that has managed that level of unbridled violence.

The most extreme violence isnt in defence of livelihoods, it's in the service of profit.

That was in the 1920s - that's not something I'm legitimately worried about.

But it is a routine occurrence to have picket lines in industrial disputes today, and to deliberately harass people who choose to go into work.

In the coal mining strikes in the UK in the 80s it got to the point where union members literally killed a taxi driver for taking a worker past a picket line.

Google aren't going to kill an Uber driver for taking me to work at Facebook instead.

Google would absolutely employ violence to defend its profits if it felt that its profits were seriously under threat and it thought violence was a viable tactic. It isnt. It's very far away from that. These things are a nuisance to them no more.

The united fruit company paid for paramilitaries to assassinate strikers in Central America.

This is a world away from dropping a brick on a taxi because your livelihood is under threat.

> Yes, they do, they lose members.

But membership is mandatory if there is a union at that corp. A union is like a service they can't ever unsubscribe from without changing jobs.

For government work especially, unions can start to take over management functions. So employees end up wanting a second union to protect them from abuses by their main union.

> But membership is mandatory if there is a union at that corp

This is untrue in every state. In some states you have to pay dues even if your aren't a member, but closed shops aren't legal.

Technically untrue, but if you are required to pay union dues then membership is effectively mandatory. It depends on State Law here. Some states are "right to work" so people can opt out, but this effectively destroys the Union. The Wagner act does not allow multiple unions or compete/cooperate so the issue in the US is framed in pretty all/nothing terms.