Are Liberals finally turning against teachers unions?

A star figure at the second annual Aspen Institute Ideas Festival -- attended by several hundred, mainly liberal intellectual and financial glitterati -- was Joel Klein, the former Clinton aide who is now chancellor of New York City public schools.
Blame teacher contracts
Klein made a riveting case that teachers-union contracts are the main obstacle to improving urban education.
"The contract protects the interests of adults at the expense of kids," he told a rapt audience, describing how it bars pay differentials based on student performance and service in difficult schools; makes it impossible for principals to fire underperforming teachers; and allows teachers to choose their own professional development tracks, regardless of supply-and-demand needs, such as those for more math and science teachers.
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