The controversy over the nomination of Betsy DeVos as secretary of education has been, if nothing else, clarifying. We now know that working to give poor kids more educational opportunities is considered a disqualifying offense for the left.

For decades, DeVos has devoted herself to creating alternatives to a public-school establishment that fails its most vulnerable students, and she earned the eternal enmity of defenders of the status quo in doing it.

The assault against her by the teachers’ unions and their allies speaks to a certain desperation. They have been steadily losing ground in the debate over educational choice at the state and local level, and now DeVos threatens to occupy the commanding heights of federal policy at the Department of Education.

Through her activism and philanthropy, DeVos has pushed for every form of educational choice, whether charter schools, school vouchers or tuition tax credits. She championed the charter-school law in her home state of Michigan and has been chair of the American Federation for Children, which is devoted to electing state legislators around the country who favor school choice. (By way of full disclosure, her husband Dick sits on the board of the National Review Institute.)

Her nomination has elicited a motley collection of charges running the gamut from the silly to the serious, if wholly misleading:

She’s wealthy. Well, yes, most philanthropists are.

She once spoke of wanting to “continue to advance God’s kingdom.” Her critics might find this less threatening if they had more than a passing familiarity with how Christians talk and what they believe (every Christian wants to advance God’s kingdom).

She doesn’t necessarily care about punishing sexual assault. This is absurd innuendo built on the $10,000 in donations that she and her husband gave to the Foundation for Individual Rights in Education.

The group is dedicated to protecting free speech on campus, but also advocates for due-process rights for the accused in sexual-assault cases.

The crux of the case against DeVos is that she is ruining education, as allegedly demonstrated by the experience of the charter schools that she has championed in Michigan. Her detractors argue that charters in Detroit in particular have been a disaster.

If Detroit’s charters are hardly world-class, they are demonstrably better than the city’s traditional public schools, which is the most relevant metric for Detroit parents. The traditional public schools have failed abysmally for generations (about half of adults in Detroit are functionally illiterate).

Jason Bedrick and Max Eden summarized the data on Detroit’s charters for the publication EducationNext. A study by Stanford’s Center for Research on Educational Outcomes found that roughly 50-60 percent of charter schools outperformed comparable district schools.

A report from a nonprofit called Excellent Schools Detroit rated 16 percent of charter schools as excellent or good compared to only 5 percent of district schools, whereas 62 percent of the district schools were weak or failing compared to 35 percent of the charters.

Finally, a report from the conservative Michigan-based think tank the Mackinac Center reached similar conclusions.

If it’s too much to ask that unions and their allies welcome marginal improvements in educational attainment in Detroit, perhaps they can at least avoid smearing it?

The other charge against DeVos is that she heedlessly opposes standards for Michigan’s charter schools, even though she has supported measures to shut down persistent underperformers and to grade charters from A-F so parents can make more informed choices.

Educational choice has been on the march over the last 20 years or so. In 1991, only Minnesota had a charter law. Now, 42 states and the District of Columbia do.

Twenty-fives states have private school-choice programs, an increase from a mere handful 15 years ago.

The ideological war over educational choice won’t be settled anytime soon. What’s clear is that poor parents value it, and that they have a friend in Betsy DeVos.

The unions will never forgive her.