kick who out of what? foreign workers wouldn't be in, or care about, your union

If a foreign worker could do what most of us do, they would already have your job, because they are infinitely cheaper.

30 years after first trying to replace all of us, they have still been unable to do so because it just doesn't work that well, even with a hybrid WHF company.

The union would kick out members who are strike breaking. It isn't possible to break the strike if you're not part of it. It wouldn't be effective to hold a strike in the first place if it was only a small minority of employees.