A Call to End Teacher Tenure

My University of Chicago colleague Timothy Knowles recently wrote a nice piece for The Wall Street Journal calling for the end of tenure in primary and secondary education.
There can be little doubt that he is correct. Tenure massively distorts the incentives of teachers. Once enacted, it becomes virtually impossible to fire a teacher. For instance, a recent BBC report says that over the last four decades, only 18 teachers in the entire U.K. have been fired for incompetence.
I see only one problem with Knowles’s argument. When it comes to getting rid of tenure, why stop with primary and secondary education? Tenure at universities is equally counterproductive. Let’s do away with it there as well.