2nd in command to sauron

[the phantom]

‘If only I could smite that foul Messenger with it, then almost I should draw level with old Merry. Well, I’ll smite some of this beastly brood before the end. I wish I could see cool sunlight and green grass again!’

Actually, that quote may not mean anything to the 2nd in command debate.

To demonstrate my point, take the Balrog. If Pippin were to "smite" the Balrog, he would not only "draw level with old Merry", but he would surpass old Merry.

But this certainly doesn't mean that the Balrog was second in command. Though it is sometimes true, the most powerful is not always the highest ranking. It takes a certain combination of skills and attributes to make a good leader/ruler, and these skills and attributes are not necessarily the same exact ones that make a good General.

(I don't have an opinion on who the 2nd in command was, just trying to add to the discussion)