A look at the enemy
It may be true that America's great sin is hubris. We must always guard against being too cock-sure of ourselves, or presuming that we are always in the right. Our power is great, and it has not always been used wisely. Self-doubt and self-criticism are moral obligations.
But there are other obligations, too, when we are fighting such men -- men who think their cause justifies any atrocity. We must never become like them. And, God helping us, with every bit of strength of muscle and brain and heart, we must utterly defeat them.
God bless the men and women at the spear's point.