The National Education Association held its annual convention this past weekend, and the Democratic presidential candidates made their pilgrimage to promise the teachers union more money—and even more money. One word we didn’t hear on stage was “Providence,” as in the Rhode Island capital city whose public schools were recently exposed as a horror show of government and union neglect.

Peeling lead paint, brown water, leaking sewage pipes, broken asbestos tiles, rodents, frigid and chaotic classrooms, and student failure were...