The arms on which a prince bases the defence of his state are either his own, mercenary, auxiliary or a mixture of the three. Mercenaries and auxiliaries are useless and dangerous. If a prince defends his state with mercenaries he will never achieve stability or security.
Mercenaries are disunited, thirsty for power, undisciplined and disloyal; they are brave with their friends, but cowards before the enemy; they have no fear of God, do not keep faith with their fellow men and avoid battle.
This is because there is no loyalty or incentive to keep them on the field apart from the little they are paid, and this is not enough to make them want to die for you. They are only too ready to serve in your army when you are not at war; but when there is a war they desert.
If mercenary commanders are skilled in warfare, you cannot trust them, because they want to advance their own greatness, either by coercing you, their employer, or by coercing others against your wishes. If, however, the commander is lacking in prowess, in the normal way he brings about your ruin.
Armed forces must be under the control of a prince or republic: a prince should assume personal command and captain his troops himself; a republic must appoint one of its own citizens as commander.
Rome and Sparta endured for many centuries, armed and free. The Carthaginians relied on mercenary arms in ancient times. They were nearly subjugated by their mercenary troops, after the first war with the Romans, even though the commanders were their own citizens.
After the death of Duke Filippo, the Milanese hired Francesco Sforza to fight against the Venetians; and when he defeated the enemy at Caravaggio he joined forces with them to destroy the Milanese themselves.
Mercenary armies bring slow, belated and feeble conquests, but sudden, startling defeat. And the result of their prowess has been that Italy has been overrun by Charles, plundered by Louis, occupied by Ferdinand and outraged by the Swiss.
Auxiliaries, the other useless kind of troops, are used when you call on a powerful state to come to your defence. In themselves, auxiliary forces can be useful and reliable, but for the person who calls them in they are usually a disaster. You are left in the lurch if they are defeated, and in their power if they are victorious.
The Florentines, completely without forces, hired 10,000 Frenchmen to reduce Pisa. However, this decision led to more problems than at any time during their troubles.
The emperor of Constantinople, to withstand his neighbours, sent 10,000 Turks into Greece. When the war was over, the Turks refused to leave; and this was how the infidels started to enslave Greece.
This kind of force is more dangerous than a mercenary army. Auxiliaries are fatal; they are a united army, which takes orders from someone else. Mercenaries are led by a commander appointed by you, and he cannot immediately assume authority to harm you. Cowardice is the danger with mercenaries, and valour with auxiliaries.
Wise princes have always shunned auxiliaries and used their own forces. They have preferred to lose battles with their own forces rather than win them with others, because they believe that no true victory is possible with alien arms. Unless it commands its own arms, no principality is secure.
Reproduced from The Prince by Niccolo Machiavelli, translated by George Bull and published by Penguin, ISBN 0-14-044107-7; #1.99. Reproduced by permission.
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