by James Q. Wilson

About the author: James Q. Wilson is the Collins professor of management at the University of California, Los Angeles, and is the author of The Moral Sense.

The central question raised by the Oklahoma City bombing is whether a free society can prevent terrorist acts. A good deal of loose talk will be heard about the subject.. .—some of it urging the Federal Bureau of Investigation (FBI) to “do whatever is necessary,” and some of it cautioning the government to “protect the Constitution.” We have been through this before, and we ought to remember what we learned in order that we not, again, lose our bearings.

Terrorist groups, like any other criminal conspiracies, are best attacked by infiltration. This means either planting an undercover agent in their...