Okay, just so we're not limiting the discussion, we don't have to consider only the Nazgul or the Third Age. Was there ever an event where the 'good' side decided to put a hit (successful or not) on someone on the other side (human royal affairs not withstanding)?
Gandalf was able to infiltrate Dol Guldur - twice, I think. Couldn't someone have done the same and taken out 'someone?!?'
Why so passive/reactive?
Even to inconvenience Sauron now and then by removing his 'Mouth' would have been of some worth, if not just to annoy.
