Joe Klein of TIME takes New York Mayor Bill de Blasio to task for agreeing to drop an education reform that caused some discomfort for his teacher union supporters.

The most damning aspect of de Blasio’s giveback is the “didn’t work” argument. We are talking about one of the ground-zero principles of a healthy school system: extra help for those who need it. If the program doesn’t work, you don’t eliminate it. You fix it. The mayor’s spokesman said the extra help would be continued in “flexible” ways. Apparently, “flexibility” is a mayoral euphemism for “I cave.” And given the current atmosphere, if it isn’t specified in the contract, it doesn’t exist. A mayor who actually cared about education would be seeking longer school days, longer school years, more charter schools (which have to be more rigorously monitored) and the elimination of tenure and seniority rules to make sure that the best professionals, not the longest-serving assembly-line workers, are in the classrooms.

Teachers’ unions are suddenly on the defensive across the country. The Supreme Court recently ruled–unfairly, I believe–that some home health care workers did not have to join the union that negotiated their contract. That could have an impact on all public-employee unions. In California, a district court judge recently threw out the state’s tenure rules. In his ruling, he wrote that the widespread protection of incompetent teachers “shocks the conscience.” A group called the Partnership for Educational Justice, which is led by former CNN anchor Campbell Brown, is filing a similar suit in New York and promises to take the movement national. Brown’s group has hired Robert Gibbs, the former Obama press secretary, to run its communications strategy; other Obama stalwarts will soon join the effort as well. Obama’s Secretary of Education Arne Duncan praised the California decision, which caused the National Education Association, the country’s largest teachers’ union, to call for him to be fired.

All of which raises an old labor-movement question for Democrats in 2014 and 2016: Which side are you on? Competent teachers should certainly be paid more, but the protection of incompetence is a national scandal, as is the unions’ resistance to teacher evaluations and charter schools, as is the quiet undermining of educational creativity by eliminating special programs for needy students.