That it has done so successfully in the past, the history of the valiant deeds of sailors and soldiers bears superabundant witness.

This courage has been brought out because it was essential.

Courage is to a man what strength is to structural materials.

No matter how physically strong and mentally equipped a man may be; no matter how perfectly designed and constructed an engine may be, neither the man nor the engine will "stand up to the work," unless the courage in the one case, and the strength of the materials in the other case, are adequate to the stress.
While perfect courage would enable a man to approach certain death with equanimity, all that is usually demanded of a man is that he shall dare to risk death, if need be.

To do this successfully, a great assistance is a knowledge that even if things look bad, the danger is not so great as it appears.