So soon as a man is armed by a sovereign government and takes the soldier's oath of fidelity, he is a belligerent; his killing, wounding, or other warlike acts are not individual crimes or offenses. No belligerent has a right to declare that enemies of a certain class, color, or condition, when properly organized as soldiers, will not be treated by him as public enemies.
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The law of nations knows of no distinction of color, and if an enemy of the United States should enslave and sell any captured persons of their army, it would be a case for the severest retaliation, if not redressed upon complaint.
The United States can not retaliate by enslavement; therefore death must be the retaliation for this crime against the law of nations.
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A prisoner of war remains answerable for his crimes committed against the captor's army or people, committed before he was captured, and for which he has not been punished by his own authorities.
All prisoners of war are liable to the infliction of retaliatory measures.
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It is against the usage of modern war to resolve, in hatred and revenge, to give no quarter. No body of troops has the right to declare that it will not give, and therefore will not expect, quarter; but a commander is permitted to direct his troops to give no quarter, in great straits, when his own salvation makes it impossible to cumber himself with prisoners.
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