Fearlessness cannot fully respond to fear because it does not recognize fear as fear.
Courage, on the other hand, is a more active response to fear. Those who display courage recognize and feel fear, but work to overcome it.
In terms of heroism, the courageous strike me as more heroic than the fearless.
Then again, perhaps the fearless have simply mastered and refined the overcoming of fear to such a degree that they have transcended it altogether.