Wealth is nice, but an enemy's center of gravity is his soul, character, mind, and faith, not his arms or his cities. As Xenophon wrote, "It is not numbers or strength that bring victories in war. No, it is when one side goes against the enemy with the gods' gift of a stronger morale that their adversaries, as a rule, cannot withstand them." On another occasion, the Persians ate on tables of gold and still had a hard time defeating 300 Spartans who ate porridge. Persia's large reservoirs of money and manpower could not bend the Greeks' disdain for the Medes and love of independence. The Greeks never surrendered.
Read the rest of the article by Jakub Grygiel here.