Editing The Prince (section)

===Defense and military (Chapters 12–14)===
Having discussed the various types of [[principalities]], Machiavelli turns to the ways a state can attack other territories or defend itself. The two most essential foundations for any state, whether old or new, are sound laws and strong military forces.<ref name=Ch12>{{Citation|last=Machiavelli|chapter-url=https://ebooks.adelaide.edu.au/m/machiavelli/niccolo/m149p/chapter12.html|chapter=Chapter 12|title=The Prince|publisher=Constitution.org|access-date=2010-01-01|archive-date=2016-11-12|archive-url=https://web.archive.org/web/20161112143208/https://ebooks.adelaide.edu.au/m/machiavelli/niccolo/m149p/chapter12.html|url-status=dead}}</ref>
A self-sufficient prince is one who can meet any enemy on the battlefield. He should be "armed" with his own arms. However, a prince that relies solely on fortifications or on the help of others and stands on the defensive is not self-sufficient. If he cannot raise a formidable army, but must rely on defense, he must fortify his city. A well-fortified city is unlikely to be attacked, and if it is, most armies cannot endure an extended siege. However, during a siege a virtuous prince will keep the morale of his subjects high while removing all [[dissenters]]. Thus, as long as the city is properly defended and has enough supplies, a wise prince can withstand any siege.

Machiavelli stands strongly against the use of [[mercenary|mercenaries]], and in this he was innovative, and he also had personal experience in Florence. He believes they are useless to a ruler because they are undisciplined, cowardly, and without any loyalty, being motivated only by money. Machiavelli attributes the Italian city states' weakness to their reliance on mercenary armies.

Machiavelli also warns against using auxiliary forces, troops borrowed from an ally, because if they win, the employer is under their favor and if they lose, he is ruined. Auxiliary forces are more dangerous than mercenary forces because they are united and controlled by capable leaders who may turn against the employer.

The main concern for a prince should be war, or the preparation thereof, not books. Through war a hereditary prince maintains his power or a private citizen rises to power. Machiavelli advises that a prince must frequently hunt in order to keep his body fit and learn the landscape surrounding his kingdom. Through this, he can best learn how to protect his territory and advance upon others. For intellectual strength, he is advised to study great military men so he may imitate their successes and avoid their mistakes. A prince who is diligent in times of peace will be ready in times of adversity. Machiavelli writes, "thus, when fortune turns against him he will be prepared to resist it."