Ken Masugi does us a great service by interviewing Fr. James V. Schall, S.J. on the Popes Regensburg lecture. The conversation defies easy summary, so Ill just give you a chunk from the conclusion:
Briefly, reason itself must be protected from the voluntarist position that no logos beyond "scientific verification" is ever possible. Once we grasp what reason is, it itself must be intellectually protected from positions that logically make it impossible. Moreover, the people against whom reason must be protected, are those in Islam, in the West, and wherever, who hold, in whatever form, that "violence is reasonable" in the pursuit of religious or ideological goals.
Implicit within this position, I would finally add, are the principles of just war and self-defense and the defense of the innocent. It is reasonable to defend oneself against those who, by the use of violence, deny any possibility of reasons own ability to know the truth of things. The use of force against theoretic violence, when it manifests itself in practice, is not itself "unreasonable violence." The use of logos includes the proper use of distinctions whereby we may understand both what is and what is at stake both in theory and in practice.