Played a game, my opponent saw my leader tried to fire on him but could not, but in that same hex I had my HQ unit with the op fire turned to short range. Am I right in assuming that the reason he could not shoot at the leader is that there was a unit alongside the leader that my opponent could not see?
That is my understanding of how it works.
Yes, in John Tiller's Campaign Series you cannot target leaders with direct fire by themselves unless they are alone in a hex. If they are with another unit, incoming fire will hit that unit if it is known and the leader may share the fate of the unit being attacked. Otherwise there won't be an attack. See section 6.0 page 69 of the manual.
In Campaign Series Middle East however you can target leaders by themselves exclusive of other units in a hex.
Hope this helps!
Thank you guys, that clears that up.