As usual, the politics of education lately seem like they’re all about the grown-ups. Teachers unions hope their walkouts in states like Arizona, Kentucky and Oklahoma will turn red states blue in 2018, while others foresee a backlash against double-digit pay raises for public employees. But behind the political machinations are deeply held views about teacher compensation.

For liberals, higher pay is a matter of social justice. Teachers make less than most other college graduates, reflecting the low status society affords women in “pink collar” jobs. Even if increased teacher pay fails to improve schooling, it’s seen as a matter of gender equity and economic fairness.

President Trump’s populist supporters look through their own social-justice lens, but they tend to arrive at the opposite conclusion. For them, teachers are a relatively privileged class: government bureaucrats with great benefits, fat pensions, summers off, tenure, reasonable pay, and working conditions far superior to what most blue-collar jobs provide. Many working-class parents also find teachers condescending and unhelpful, as Joan Williams explains in her 2017 book, “White Working Class.”

A third approach is the technocratic one taken by education-policy researchers. Two economists, Thomas Dee and Dan Goldhaber, wrote in a report last year for the Brookings Institution that teacher shortages “are not a general phenomenon but rather are highly concentrated by subject,” particularly in math, science and special education, and in low-income areas. They advocate raising teacher pay to address specific shortages, but they say that across-the-board increases would spread finite resources too thin.

All three of these ways of thinking about teacher pay are inadequate. A better approach would start by recognizing three very conservative facts: History matters, teachers matter, and you can’t get something for nothing. Together, they point to a policy of significantly higher teacher pay—but only in exchange for real reforms to improve teacher quality.