Multiplicitous federal policies and programs threaten privacy — data mining, the REAL ID Act, National Security Letters, etc. — and they threaten trade and commerce too. The link among them, of course, is the threat of terrorist attacks.

An essential part of any security discussion is to get a handle on the threat. Cato Unbound devoted some energy to that problem last September with exquisitely rational analysis from the Ohio State University’s John Mueller, while former Inspector General of the United States Department of Homeland Security Clark Kent Ervin argued, “I’d Rather Err on the Side of the Believers.”

Now the RAND Corporation has released a report called “Exploring Terrorist Targeting Preferences.” According to the press release announcing the report, it finds “little evidence of a coherent al Qaeda strategy for U.S. attack.” The report explores four different theories of al Qaeda’s motivation, toward the end of determining its likely future actions.

I don’t have the capacity to critique the report and I don’t think it ends the inquiry, of course. Al Qaeda’s motivation should be a matter of continuous study, along with all other threatening entities. The capacity of threats to follow through on their intentions should be the subject of equally searching, continuous study.

But I think it is essential to have reports like this issued and discussed. They are part of getting the threat of terrorism in perspective and solving the security dilemmas created by terrorism. These problems are not easy, but they are fully susceptible to solution consistent with our Constitution and our tradition of liberty.