What do you call someone who, merely by their presence, gives a morale boost to the people he is responsible for? What about someone who gains power from being supported by their troop?
If possible I would like to have word with military connotation, but a more "civilian" approach is also interesting.
EDIT: Jez gave a lot of interesting examples, but I am also interested in nouns, and all of Jez's example can't be "translated" into nouns that easily.