I'm curious, do you believe the Khan Sheikhoun attack was a rebel false flag operation (as implied by Postol in his articles), or a result of a Syrian airstrike hitting a rebel chemical weapons storage facility (as reported by Hersh)? At various times the Syrian and Russian governments have pushed both theories (although in the case of the latter scenario, they have provided different details from what Hersh reported).
I tend to think that the two different accounts are not exactly mutually exclusive. We have to be cognizant of propaganda. The Syrians and Russians might say it was a false flag. Maybe it was, maybe it wasn't. Maybe the Al-Qaeda or whatever they were calling themselves at the time, were hoping for an air strike, it's even possible they leaked the information that lead to the air strike themselves. We also have to be aware that not everyone has all the information, and the only people who do, are those who were on the ground. Hersh can report what he knows from his intelligence sources. The Russians and Syrians can report what they know, but you can expect a little bit more, how can we put it, artistic liberty, with their account.
At the end of the day, you've got to look at all the evidence that we do have, and then try to contextualize it based on what we know. Who stands to gain from such an attack? Who stands to lose? What are the motivations for such an attack? What is the character of the primary participants. What credible information do we have? How do we value that information? Among other questions to ask. When I run down this list, I see Assad as the one who has the most to lose. I see the Jihadist groups are gaining the most. I see Assad as someone who while ruthless, is probably not suicidal, and will act to preserve his position. I see Al-Qaeda as someone who has nothing to lose and everything to gain, and has no qualms about sacrificing civilians, enmass if it meets their goal. What is the outcome of a gas attack by Assad, international condemnation, and potential intervention. This isn't even taking into account the western medias support for the ouster of Assad, or any intelligence apparatus' that may be in the back ground trying to facilitate this.
The report that implicated Assad, had no evidence. It's a "I think, presented as fact" piece. The doubts over who was responsible was raised by Hersh who has intelligence sources telling him that it wasn't Assad. There is no concrete evidence on either side, so we're forced to look at questions and questions like the ones I posed in the previous paragraph.
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