The power of the teacher unions
Wearing pastels doesn't make Darth Vador any less evil and talking about "the children" doesn't make unions any less self-interested.
Not only do the teacher unions have more power and influence than the largest corporations on earth, but they protect bad teachers in the classrooms and block meaningful reforms that benefit students. Bad teachers pay dues and, well, education reforms decentralize power and reduce union influence.
Read the Education Next article titled "Invisible Ink in Teacher Contracts" to learn more about the power and influence of the teacher unions.