> It's not an assumption that it must, it's a recognition that very likely, it will. To add to everything you just said, the NLRA sets very rigid rules regardi

> It's not an assumption that it must, it's a recognition that very likely, it will. To add to everything you just said, the NLRA sets very rigid rules regarding how unions can form and how employees and employers can interact with them. So you can't just charter it however you want and assume all the problems are solved - the NLRA imposes a number of requirements and protections for the union (not the members, but the union itself as a corporate structure) which way be at odds with the employees. As a result, once a union forms, it's very difficult (practically) for its members to deunionize, even if a majority of the membership opposes the union representing them. So people are very hesitant to go down a road which is essentially seen as a one-way street, except as a last resort.