Is not defined in singular terms. There is no one definition of courage that applies to the whole of
(wo)mankind. If I am not afraid to die, if I actively and aggressively want to die then picking up my weapon and heading into the battle is less an act of courage than the exercise of the means to the desired end.
Courage does not operate on predetermined degrees. There are those among us for whom the tiniest step outside their comfort zone e.g. leaving the house and going to the grocery store, requires levels of courage that some soldiers will never experience in their lifetime.
But the choice to exercise our own version of courage, the act of taking that tiniest step is the very first stone put in place that eventually leads over the rest of a lifetime to the kingdom of Rome.