Editor's note: Timothy Stanley is a historian at Oxford University and blogs for Britain's The Daily Telegraph. He is the author of "The Crusader: The Life and Times of Pat Buchanan."
(CNN) -- When I read a headline that said thousands of teachers had gone on strike, my immediate reaction was, "What has Scott Walker done now?"
But, surprisingly, the latest elected official to do battle with a public-sector union isn't the Republican governor of Wisconsin. It's Rahm Emanuel, the Democrat mayor of Chicago and President Obama's former chief of staff. The struggle is significant because it challenges the orthodox narrative. It isn't just tea party Republicans who are tangling with unions. Democrats are getting pulled into war with their old allies, too.
In the popular imagination, Chicago is a heartland of New Deal liberalism, a place where even the dead vote Democratic. For decades, the city machine has bought off unions with sweetheart deals. Emanuel tried to do something different. He wanted to introduce merit pay and an extended school day, and there was every sign that he'd get both because the local teachers' union required the support of 75% of its members to authorize a strike. But Emanuel didn't bet on the anger of rank-and-file teachers; 90% voted to walk off the job.
The union sees itself as part of a wider struggle on behalf of the middle-class, holding the line against economic dinosaurs and the quislings of big business. Not only is it harder to make that argument against a Democratic mayor, but there's also evidence that Chicagoans are not getting value for their money from the public school system. According to figures from the U.S. Census, the average resident makes about $47,000 a year, while the average teacher gets paid $76,000 a year. (Union sources place the figure at around $71,000, which is still the second highest in the country.)
Given how well they get paid, you might imagine that Chicago's schools are international centers of excellence. Sadlly, according to a report from the Washington Post, "Fourth-graders in Chicago performed an average of nine points worse than the big city average and 16 points worse than the national average on the math section of the National Assessment of Educational Progress (NAEP), the national gold standard for measuring learning."
So is Emanuel -- known by Chicagoans as "the Missile" -- the real champion of middle-class tax payers? Yes and no. To buy the strikers off, he offered them a 16% pay increase over the next four years, even though Chicago's school system faces a $667 million deficit this year, which is predicted to hit $1 billion in 2013. The union turned the offer down, and Emanuel looks weak.
The strike probably won't affect the presidential election. Illinois is going to vote for Obama, and teaching unions contribute roughly 95% of their donations to Democrats. But this strike isn't an isolated story of a lone liberal taking on the teachers. On the contrary, it follows a national pattern.
The headline teaching union battles have mostly been with Republicans: Gov. Scott Walker in Wisconsin and Gov. Chris Christie in New Jersey. But some Democrats are taking up the cause of education reform, too, to the frustration of labor activists. Obama has endorsed the Race to the Top program, which links teachers' evaluations to SAT scores and would allow charter schools to replace failing public schools.
Los Angeles Mayor Antonio Villaraigosa backed school privatization and has gone so far as to call teaching unions an "unwavering roadblock to reform." Newark, New Jersey, Mayor Cory Booker has supported Christie's program of school reform. Massachusetts Gov. Deval Patrick endorsed a measure that curbed teachers' seniority programs. One result has been that in some races, teaching unions have backed friendly Republicans over reform-minded Democrats.
Why are Democrats doing this? As in Chicago, a large part of the reason is that they want to link merit and pay to improve test results for middle-class students -- a great issue to run for election on. But another cause is probably the recession. Like their Republican counterparts, Democrats are being forced to confront the unions to bring teachers' pay and benefits back down to a sustainable level, or at least a level that won't require job-killing tax hikes.
There are exceptions. Maryland Gov. Martin O'Malley has tried to pass the cost of teachers' pensions onto the counties rather than significantly reduce them. No wonder he is so popular with their unions.
It's unlikely that either Republican or Democratic politicians really want these bitter fights with teachers, which leave schools closed and make elected officials look either radical or incompetent. But America's sluggish economy has forced both parties to take bold, unpalatable decisions.
As Emanuel is famous for saying, "You never want a serious crisis to go to waste" -- and the most imaginative officials have tried to use budget cutting as an opportunity to improve test scores and retire bad teachers. For that, they deserve the praise of the tax payer. Nevertheless, the reforms are ultimately compelled by economic realities beyond everyone's control. These days, austerity isn't just a tea party slogan. It's an inescapable necessity.
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The opinions expressed in this commentary are solely those of Timothy Stanley.