9/11 "Conspiracies" and the Defactualisation of Analysis: How Ideologues on the Left and Right Theorise Vacuously to Support Baseless Supposition is a fascinating piece analyzing the various theories surrounding the failure (or success) of the US intellgence community in averting the 9/11 tragedy, the anthrax case, and other post-9/11 politicized items. This is an excellent article of unbiased research and reporting.
"...the FBI has never been keen to identify the perpetrator [of the anthrax letters] because that perpetrator may, in fact, be the U.S. Government itself. Evidence is mounting that the source of the anthrax was a top secret U.S. Army laboratory in Maryland and that the perpetrators involve high-level officials in the U.S. military and intelligence infrastructure? Forget unfounded conspiracy theories. The evidence is overwhelming that the FBI has consistently shied away from pursuing the anthrax investigation [under government pressure]."
"...the likelihood of political inaction being behind the administration's failure to foil the Al-Qaeda plot, in itself implicates the existence of a web of strategic and economic influences acting upon the political establishment, which resulted in such political inaction. And given that this is a far more tenable and probable possibility than mere 'incompetence', then it is essential to investigate the matter more thoroughly - including specifically an evaluation of the information (and what was done with it) about the 9/11 attacks available to the U.S. intelligence community."
At the very least, its entertaining.