The Pentagon renovation

Like many others, I find the claim that a Boeing 757 hit The Pentagon questionable.
The perfect, circular C-ring punch-out hole suggest that a warhead (missile) was used.
If that would be the case, then why was the missile / cruise missile fired?
Why did ‘they’ attack The pentagon? I keep asking myself this question over and over.

Could it be possible that the whole operation was planned and partly executed from inside The Pentagon? Could it be possible that a small group of people inside The Pentagon (high-ranking military, NSA, CIA) used that part of the building as a sort of operations centre? And that all evidence was destroyed in the attack? That particular section was ‘closed off’ and under renovation.

One can argue that it would be to risky to plan such an operation from inside The Pentagon.
On the other hand: nobody was expecting anything and therefore The Pentagon would have been a perfect and convenient place to ‘hide and prepare’.

- Any other place, a rented building for example, would raise suspicion. People walking in and out, especially well know figures;
- No need for phone calls, travelling (questions);
- No risk of being caught – the building is heavily guarded from outsiders;
- If a group of people where seen together going in or out that particular part of the building, it would not raise suspicion – they where suppose to be there.

I guess this idea is to farfetched … So my question is: why do you think The Pentagon was attacked - if it was indeed an inside job?
If they needed it to scare the masses, they would have used a Boeing 757 and they certainly would have provided the general public some horrifying videos.

On Edit: spelling

The Pentagon is supposed to be the very core of our military infrastructure, and they (the terrorists) attacked it - they got through the invisible wall of security Americans are used to. It's a kind of reinforcement, to make sure you want to kill them before they kill you, IMO.

I do, however, think a real plane hit the Pentagon - Flight 77 I believe.