I get the frustration with aspects of the 9/11 truth movement that are posted here:
1) One issue agreement. So long as X questions 9/11 their views on other issues don't matter.
2) Big tent. So long as X questions 9/11 the focus of their skepticism doesn't matter.
IMO issues with the 9/11 truth movement can only explain so much. Other factors:
1) Secrecy. Abuse of classification procedures, especially when "classified for national security reasons" is exploited to conceal criminal activity.
2) Propaganda.
3) Authoritarianism. Feeds off the propaganda to the point where authoritarianism=patriotism.
4) Establishment consensus to preserve the status quo. For example, the rule of law doesn't apply to high ranking officials. In fact, their criminality is spun as good faith criminality!