I guess for the same reason they don't bring up the OKC connection, TWA800, Ron Brown's murder, etc. New Tone.
I trust you know about Jack Cashill's latest video, 'Mega Fix'?
What's your opinion? Because it will embarass the country? I think the powers that be don't want anything embarassing to come out because it reflects on them.
I haven't seen anything on Cashill's book, but another guy named Spence (?) has just come out with a book covering all of the things the government has covered up, including all those things that you mention.