Here’s what we know, factually speaking (I mean, if you believe in physics):
- WTC7 came down not due to an office fire but either due to a controlled demolition   [3.1] [3.2]  or alien technology that simulated a controlled demolition. Occam’s Razor suggests no aliens were involved.
- Our security apparatus knew of the attacks in advance and not only ignored them, but appeared to go out of their way to do so. There are other interesting public-knowledge factoids indicating foreknowledge of the attacks, but you can look those up yourself.
- WTC7 was home to the CIA, Secret Service, and Department of Defense  [4.1] [4.2], and was the last building to go down (the first was the building furthest away from WTC7).
So, from that it’s rather easy to piece together a semblance of what happened and why whistleblowers are hard to come by, even though some (like Sibel Edmonds and others) do exist:
- A very tiny group at the top received reports of attacks that it knew were going to happen, and likely instigated/setup in the first place (as the FBI/CIA is fond of doing).
- They ignored these reports because they wanted the attacks to happen, as that would give them the needed excuse to get oil for America.
- Thanks to the magic of need-to-know and compartmentalization, this group was able to get others to install explosives in all the buildings ahead of time in order to destroy evidence and create the shock value needed to unify the country to support a new war against whomever.
- The people who installed the explosives (which could’ve been installed long before 9/11) were probably told some BS about why they were doing it and then were later shot or disappeared.1 The BS could be different depending on the building. For example, it would make sense to say that WTC7 might need a self-destruct mechanism to protect the sensitive state secrets within it, and even those working within the building during the attack could be told that the area was under imminent attack and therefore the building had to be evacuated and destroyed just in case.
So, the “Inside-Inside” of the title of this post suggests that a very small group (perhaps as small as 3 or 4) knew everything that was going on, while others supported their efforts without questioning or understanding their plans. This same group prevented information from one branch of government (e.g. Sibel Edmonds forwarding warnings of terrorist plots) from reaching a different branch of government (e.g. the ones responsible for acting on those warnings).
The “Outside” part just means that people who were outside of the government (the terrorists) were allowed to attack America so that the “Inside-Inside” would have the excuse it needed to invade Iraq and get us that oil to prevent our infrastructure and war-machine from collapsing (or some-such).2
EDIT November 23, 2016: Former NIST employee speaks out!
— Greg Slepak (@taoeffect) November 23, 2016