Should teacher's salary be based on merit pay?

The biggest gripe that the striking Chicago teachers have is the proposed requirement of having part of their pay based on student scores on standardized tests. I am not myself a teacher, but I am an academic by inclination. My first reaction to merit pay is that it is demeaning to teachers. Teachers should be treated like professionals. We don’t pay doctors, lawyers or engineers based on merit pay. We have enough of a problem retaining qualified teachers, without further humiliation. Instead of dismantling the No Child Left Behind fiasco, we are building on it.

There is an alternative. For the last several years the Finnish school system has finished at or near the top among Western school systems in international testing. There are of course important differences between Finnish and American cultures, but it is worth noting that the Finns achieve their school success by essentially doing the exact opposite of U.S. schools. Why is nobody paying attention?