The Chicago Teachers Union’s attacks on charter schools are to blame for the upcoming closure of the Chicago High School for the Arts.

At least three Illinois teachers unions threatened to strike at the start of this school year. Keeping students out of class so unions can get their way should be illegal in Illinois.

District 146 Educators Council has voted to authorize a strike. If an agreement is not reached, teachers in Tinley Park could strike as soon as Sept. 22.

Teachers in the 10th-largest school district in Illinois may be on the picket lines instead of in classrooms with students on Sept. 18. Romeoville and Bolingbrook teachers are paid more than the state average but are pushing for more.

The Chicago Teachers Union exerts power not only over the city of Chicago, but also statewide. Southern Illinois schools and their funding is the target of CTU leaders’ latest attack.

The Chicago Teachers Union is more political machine than labor union, putting nearly $1.8 million into the campaigns of 84 of 177 current lawmakers since 2010. But it may be losing its hold on Springfield.