No Islamic terrorism threat in U.S.A.?

Several news sites have decried a report that omits Muslim extremism as a main source of domestic terrorist threats. See Bill Gertz's piece for example:  Domestic threat assessment omits islamist terrorism/   The subtext on this is that many on the right believe the Obama administration has whitewashed the story of Islamic-motivated terrorism in this country.  I haven't gotten my hands on this report yet, but I'll suggest a few ways to think about this problem.

• The FBI does not deny the problem of Islamic terror.  Check out the Most Wanted List and see if you can detect a pattern:  FBI's Most Wanted
• The Feds are reluctant to call something Islamic terrorism if the motive is unclear.  Perhaps that's why the report doesn't finger the Tsarnaev brothers as "Islamic" terrorists.  As far as I know, they have not been credibly linked to Al Qaeda or any other organized movement.  By the FBI's definition, domestic terrorists "lack foreign direction." 
• One of the problems is the issue of the lone operator,  or "leaderless resistance," which has become an Al Qaeda strategy now.  This, as far as I know,  originated in the American White Supremist movement with "The Turner Diaries."  Are they really politically motivated terrorists, or just dangerous psychotics?
• For a great read that makes sense of the whole issue, and notes the ambiguity of the FBI's definition, see the Congressional Research Service's report on Domestic Terrorrism  The CRS is one of the best-kept secrets in the federal government. 

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