While I agree with your conclusion that this is bunk, I see some problems here.
In fact, this "FBI circular" has nothing to do with the FBI.
It's from the Columbus, Ohio Police department...
To be fair, the article does say that you can find the brochure on the Columbus PD website. The brochure itself is part of a Communities Against Terrorism initiative, which is funded by the Bureau of Justice Assistance's State and Local Anti-Terrorism Training (SLATT) program. I found a similar brochure at another Terrorism Early Warning Group webpage:
https://www.hamiltoncountyohio-tewg.org/downloads/. Even if these brochures are produced locally, I don't think it excludes the possibility that the author received his information from the federal level. There's no evidence to prove or disprove FBI involvement so saying that it has
nothing to do with the FBI seems premature. There's no formal connection between the BJA and the FBI that I'm aware of, at least; but at the same time, the FBI does work with Terrorism Early Warning Groups.
Before I move on, it's worth pointing out that this is just one brochure of about 25 that were sent out in 2010. Infowars actually covered them in article that year, but only mentioned the one on tattoos:
http://www.infowars.com/fbi-agents-...very-time-they-put-someone-on-the-watch-list/. There was a bit of a stir over these brochures in 2012; I'm a bit disappointed that no one seems to remember.
As for the bunk itself:
FBI calls half of populace with 9/11 doubts potential terrorists
As the digitaljournal article states, the study only found that 10% of the population believed that it was caused by the government, the other 38% of that 48% merely agreed with the statement: "I have some doubts as to whether the government's account fully explains everything". That could mean a lot of things. Furthermore, the brochure just says that an attitude indicator is conspiracies theories about westerns, where 9/11 is just one example. There's a strong current of anti-American conspiracism in the middle east, which no doubt leads to the kind of shame and humiliation that causes religious violence (see James W. Jones' research on religious violence, though the connection to arab conspiracism is my own speculation), so it's not too surprising that this would be included as an indicator. It also says later in the text: "some of the activities, taken individually, could be innocent and must be examined by law enforcement professionals in a larger context to determine whether there is a basis to investigate". The brochure is not saying that 9/11 truthers are terrorists, but that believing in anti-Western conspiracies is one of several traits that may help identify islamic sleeper cells. Also, it's clearly written for a general audience.
