ORAC,
You mentioned the concept of the existance of air supremacy while a tangible and operational surface to air threat is maintained by the enemy.
I contend that air supremacy is not attained until all counter-air threats are effectively removed. I do agree though that air superiority can be attained and maintained while enemy SA is still operational (you go round them).
I believe Air Dominance describes a temporary situation when the superior air power is in the process of destroying every counter-air asset by the enemy. The transition phase between air superiority and supremacy...IMHO