What makes a good leader?

"It made me sad, watching the tight-necked, pop-eyed, clenched-jawed, eyebrows-twitching, shoulders-heaving, ghoulish-smiling, rapid-blinking John McCain go from pale to translucent as he flailed away on TV last night, to remember the man I saw at a town-hall meeting in Salem, New Hampshire, last January—years ago. Back then he was witty, he was relaxed, he was appealingly combative, he was generous. The contrast now is so severe that it makes running for President seem like a personal disaster on the scale of a prolonged nervous breakdown leading to physical and psychological ruin. This campaign has done something terrible to McCain. And it’s entirely his own fault. Character is fate.
Obama has passed through the same travail along an even harder road and has been elevated. In New Hampshire one of his advisers, a former Clinton official, told me that he had come around to Obama after reading “Dreams from My Father” and then meeting its author: here was an entirely centered, self-aware man. At the time I thought this was a pretty impressionistic basis for a major political decision. Now I see what the adviser saw. Obama’s character is a political triumph. His cool, unlike McCain’s tic-filled anger, is tactically deployed; throughout the campaign it’s become his main weapon against crisis and attack. " - George Packer, The New Yorker , 17th Oct, 2008.
In the face of this current election as approval seems to swing in favor of the cool and compost stature of Obama, my question is - What is it that we are looking for in our leaders?
As for me, cool without being cynical, self assured without being self righteous, decisive without being judgmental/ impulsive, argumentative without being accusatory, combative without being offensive makes a great leader.
What made a great King largely depended upon his ministers or court advisors, King Aurthur had his Knights of the Round Table, Akbar had his. As far as, wisdom and leadership abilities are concerned, a King's job is to manage and delegate orders, to distinguish a not-so-great advise from great one and to listen to the right person at the right time.
It remains the same today for our leaders.