Over the past few decades a growing awareness has developed in the science education community about the educational power of the history of science. Yet, the historical approach is not implemented in many ministries of education policies. In order to investigate what factors contribute to this, we have conducted a survey of attitudes toward the history of physics amongst a large sample of Italian secondary school physics teachers who received in-service training programs in physics education. In particular, we have explored teachers' opinions about the meaning and usefulness of the historical approach, as well as their self-assessment of expertise. We have found that these teachers do not question the validity of the historical approach. A minority of them, however, fear that factors like the lack of adequate preparation in the undergraduate years might compromise the outcome of this approach.