When McAlvey, as a labor organizer, has to "figure out how to build to 90 percent or greater unity with unbreakable solidarity and a tight, effective structure", this is within very sort of bubble she discounts as the domain of activist mobilizers.
Note the confounding here of unity and solidarity. That 90% unity threshold speaks to the extent of shared values within the bubble of a shared workplace. Solidarity is usually about common objectives even especially despite disunity of values.
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