“While we don’t promise equal outcomes, we have strived to deliver equal opportunity,” proclaimed Barack Obama in 2014. In that year’s State of the Union Address, he also declared: “Opportunity is who we are, and the defining project of our generation must be to restore that promise.”

Across the aisle, Paul Ryan criticized Obama while expressing the identical sentiment. “He’s shifting us away from the American idea — from a society of upward mobility — and we’re talking to each other more in class terms. Instead of focusing on equality of outcomes we should be focusing on equality of opportunity.”

This exchange is just one of countless examples. Equality of opportunity is everywhere in American political discourse, generally treated as axiomatic by Democrats and Republicans alike. As Dylan Matthews of Vox put it in 2015: