One of my main criticisms of the mediocre Medal Of Honor was the lack of feeling involved. Indeed, I felt similarly playing the Modern Warfare games, whenever it became apparent that my actions weren't exactly crucial to progress (I followed behind on No Russian, without firing a shot). This is something "T2DMrBungle" discovered when playing Call Of Duty: Black Ops, specifically the first mission, played on the disturbingly named "Hardened" difficulty level. It's a fifteen minute video during which he doesn't fire his gun once. It's below.
As he narrates near the beginning, if you don't have time to watch all 15 minutes, skip to around 13:50. I think this is perhaps the point where people should maybe be asking to have slightly more of a role in their games?