Ignored the difficult (and first!) one, didn't ya? Very pre-teen like. :-D
There's nothing difficult about that. The USMC has an active investigation of a cover-up. It has been reported, about as officially as it can be at this point, that these civilians weren't blown up by an IED - which was the 'official' position until it was found to be otherwise. I guess you can claim that the initial claim that they were blown up was correct, even though no one really believes that, and if you believe that then perhaps everything else - the investigations, the witness testimony, etc. - was just created out of thin air by the media. I guess you would also believe that the USMC would open an investigation of a cover-up without any evidence whatsoever of a cover-up and based solely on a media report that was completely fabricated.
Yes, I would still say that would be delusional.
It may be that the story is not as presently reported. There may have been other circumstances that led these Marines to view those civilians as a threat, and led to their shooting. If that is the case, why'd they claim afterwards that the civilians were blown up?