Having spent the better part of a week asking teachers why they’d risk a public backlash by going on strike, I’ve concluded that the answer is best summed up by what one told me at their Labor Day rally: “Mayor Emanuel’s pushed us to the limit. He’s the world’s biggest asshole.”

I just read an open letter “To the Leaders of the Chicago Teachers Union from Leaders of the Faith Community.” It’s an ad in the Sun-Times, published before the strike and signed by various clergymen with close ties to the city government, calling on teachers to do what’s right for the kids and call off their strike.

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Of course, by writing this letter they’re very much siding with the mayor. Because if the union calls off the strike they lose what little leverage they have to force the tough and powerful people who run this city to give them even a fraction of what they want.

Traditionally, CPS has been a top-down, vaguely militaristic system in which central-office bosses issue mandates like Zeus from above.

Into this world marched Mayor Emanuel, like Napoleon invading Russia.

Meanwhile, his only official meeting with CTU president Karen Lewis was the one last August 2 when they had their infamous squabble. He wound up telling her “Fuck you, Lewis.” And she told him—well, we’re not sure what she told him. But I’m sure it wasn’t pretty.

The mayor also had his appointed school board rescind the raise the previous board had negotiated with the union on the grounds that the system was too broke to pay it. Even though the system wasn’t too broke to raise the pay of CEO Jean-Claude Brizard—and most of his central-office appointees—over what their predecessors were making. Just as their predecessors got a boost over the people before them, and so on.