Re: Why was O'Brien not an officer?
The O'Brien rank issue has been discussed many times before, he clearly wore Lt. pips throughout most of his apperances on TNG.
In Trek sometimes position is more important than rank. So his position as Chief of Operations gave him authority despite being a NCO.
On the continent of wild endeavour in the mountains of solace and solitude there stood the citadel of the time lords, the oldest and most mighty race in the universe looking down on the galaxies below sworn never to interfere only to watch.