Betsy DeVos favors school choice and helped pass Michigan’s first charter-school bill.

After Donald Trump nominated Betsy DeVos to become education secretary, teachers union honcho Randi Weingarten tweeted: “Trump has chosen the most ideological, anti-public ed nominee since the creation of the Dept of Education.” Since what’s good for the unions is often bad for the schools, and vice versa, Ms. Weingarten’s apoplexy is reason to cheer. Ms. DeVos is chairwoman of the American Federation for Children, an organization dedicated to helping parents choose the best school for their kids. Ms. Weingarten leads the American Federation of Teachers, which is focused on what’s best for the adults. Detractors say Ms. DeVos is opposed to public education. But she told an interviewer in 2013 that her definition of educational choice includes schools of all kinds. “What we are trying to do is tear down the mindset that assigns students to a school based solely on the zip code of their family’s home,” she said. “We think of the educational choice movement as involving many parts: vouchers and tax credits, certainly, but also virtual schools, magnet schools, homeschooling, and charter schools.” In the early 1990s, Ms. DeVos and her husband, a former president of Amway, were involved in passing Michigan’s first charter-school bill.

Ms. Weingarten brings a different set of priorities to the education debate. She has fought to keep persistently failing schools open because they still provide jobs for her dues-paying members. She has fought to ensure that government officials, rather than parents, decide where a child attends school. Union influence over education policy in the U.S. is unrivaled, and Ms. Weingarten prefers it that way. Her top concern is better pay and working conditions for her members. Students don’t pay union dues. That doesn’t make her a bad person, but it should cast doubt on claims, too often swallowed whole by education reporters, that union interests are perfectly aligned with those of students and families. A union-negotiated work rule that says teachers can’t be evaluated by how much their students learn is a job-protection measure, but it obviously harms kids and school quality.

Education philanthropists often work to accommodate the teachers unions. Ms. DeVos chose to fight them head on by backing political candidates who support school choice, the same way unions support candidates who don’t.

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