[T]he Romans, observing troubles from afar, always found remedies for them and never allowed them to develop in order to avoid a war, for they knew that war does not go away, but is merely deferred to the advantage of others.

Machiavelli explains that a wise prince never runs from a war, for the simple reason that the war will inevitably follow. Using the Romans as an example, he presents their paradigm of preemptive strategies: Analyze the conditions for conflict and address them before they develop into a full-fledged war. For example, a ruler can invade a threatening territory to put down a potential invasion, or the ruler can wait and the war will come to him. Fighting a war on the enemy’s territory preserves the well-being of one’s own people. Machiavelli believes in pressing this advantage as he repeatedly asserts that a prince must always have his own men and be ready to make war. According to Machiavelli, princes gain and keep power through making war, a prince’s primary duty.

I judge those princes capable of standing on their own who have an abundance of men or of money, so that they can put together a sufficient army and fight a battle in the field against anyone who comes to attack them.

Machiavelli gives his advice about the essential resources a prince must bring to the table. He equates a self-sufficient prince with someone who can supply his own army. Preparing for attack functions as a deterrent against attack. In the event of war, the army must be of size and quality to defeat any challenger. In Machiavelli’s practical view, maintaining a standing army capable of beating any enemy takes either many men or enough money to hire soldiers.

I say, then, that the arms with which a prince defends his state are either his own, or they are those of mercenaries or auxiliaries, or mixed troops. The mercenaries and auxiliaries are useless and dangerous[.]

Machiavelli wrote The Prince in an attempt to make Italian princes comprehend new ways to make war. He fervently asserts that a prince will fight best and most successfully with his own army rather than one consisting of auxiliaries—troops borrowed from another principality—or mercenaries—troops who fight for money, regardless of country of origin. In Machiavelli’s time, many if not most wars were fought with mercenaries or auxiliaries. Machiavelli proceeds to point out numerous times that using these troops led to ruin, especially for Italian states. His ideal prince will lead a home-grown, patriotic Italian army.

[I]f two powerful neighbors of yours come to blows, either they are such that if one of them wins, you will have to fear the victor, or you will not. In either of these two cases, it will be more useful for you to declare yourself and wage an honest war[.]

Here, Machiavelli warns against staying neutral when neighbors wage war. He promotes choosing a side, even if the choice results in joining the losing side. A principality stands to gain nothing from staying outside the conflict because both sides will no longer trust a party who remains neutral and therefore would not come to his aid in the future. Again, Machiavelli imbues a vice—war—with virtue because the supposed vice meets a greater goal of securing a prince’s rule. War helps him maintain friends and allies for future conflicts which will inevitably arise.