The Arthrashastra indicates there are three kinds of aggressors who would dominate another: those whose aggression is motivated by greed, those whose aggression is motivated by hatred, and those whose aggression is motivated by a sense of Justice. There exists a duty to rebel against an aggressor who would dominate you.
When dominated by one who is motivated by greed, use their greed to dominate them in return: a greedy person desires to keep what they have taken safe and well-maintained, and this results in fear, as they cannot keep all they have taken safe or well-maintained. Fear may be kindled toward the self-destruction of the aggressor by a skilled diplomat, a Brahman. Yet this is the lowest form of rebellion, and if it is ineffective, the Brahman or Diplomat should engage to do more. By the skill of the Diplomat, the aggressor may come to desire more, and the desire will cloud their judgment in exchange. This will permit one skilled in business, a Grihasthi, to weaken the aggressor's strength through economic warfare: either by taking from the aggressor their wealth, or by overtaxing their ability to maintain and protect what wealth they have stolen, resulting in self-destruction of the aggressor. The Kshatriya Vanaprasthi should utilize the greed of the aggressor by gifts and homage through the force of faith: for example, the homage of cavalry might be demanded, yet the gift of unwieldy horses will weaken the aggressor, or lead to their self-destruction; if the dominator were truly worthy of the homage and devotion of the people, they could wield any gift made by them. The Sannyasi, or Sudra, being the object of desire of the greedy aggressor, should even yet serve the one who would dominate them. However, they must sabotage those who would dominate them, or even by laziness and purposed unskillfulness lapse in their service. This represents the highest act of rebellion and is practiced by Hatha Yoga, strength and control over body and form.
When dominated by one motivated by a sense of Justice it is best to devote one's self to Justice as well, and argue the Dharma, teaching them the correct worship of Justice is not in the violation of Justice through domination. This is best done by logic, through Diplomats. Yet is also possible through economic warfare by Sudras and Vaishyas, such as boycott and substitution of supply, etc - just as the Vaishyas and Brahmans work closest together for the rebellion against the greedy aggressor, here the Vaishyas and Sudras work closest together. Yet there is opportunity for Kshatriyas as well - through an extreme (overly strict) adherence and devotion to the Dharma of Justice, so that the aggressor loses their desire for Justice, or their ability to enforce it. This is accomplished by the force of truth, practiced by Jnana Yoga, strength and control over mind, the comprehension of reality and truth.
When dominated by one motivated by Hatred, there is only one response: and that is rebellion by force. Led by the Kshatriyas, the dominated people must resort to the force of holding on. They must hold on to their old ways, their old friendships, their old behaviors, their old customs and language, their old culture and songs; they must disregard the one who would dominate them and, if it becomes possible, flee the dominator, regroup and reconquer what was theirs - by diplomacy, force, economics or in the service of a strong ally. Yet in every case, the efforts of a solitary warrior will be the most effective: for the hater will thereby come to understand the power of an individual, and behold the number of individuals who stand against them. The Soldier must become a commando or spy, causing unspeakable damage and intrigue, as if jealously defending a lover. The Diplomat must communicate to the masses. The Industrialist or captain of Commerce must become strong enough to resist domination - each like a proud King. And each Sudra must preserve and persist, heroically lovingly devoting themselves to serving properly, without fear or regard to the aggressor. This is the highest duty: if everyone merely disregarded and persisted despite the hatred of the aggressor, the aggressor would have no power. This is accomplished by the force of love, practiced by Bhakti Yoga, strength and control over the heart.
When first encountering an aggressive opponent is is necessary to discover what type of aggression motivates them, so that proper defense can be made.
Therefore, before hostilities begin, ask for peace to determine what they ask for. If they ask for things or for homage, you may be certain they are motivated by greed. If they are motivated by Justice, they will demand duty, correct behavior, or the restitution of wrong. If they are motivated by hatred, they may pretend toward either of these, or demand nothing at all. Yet the hateful enemy will not come to terms of peace. It is right to purchase peace so long as the cost of peace is less than that of war, and is not unbearable to the point of representing injuries which cannot be recovered from. It is right to seek the adjudication and mediation of a disinterested third party. But it is never right to submit to hatred.
The first phase of warfare therefore is the attempt for Peace. The second phase is understood to be an act of rebellion: all self-defense is an act of repelling one who would dominate you. The goal is the restoration of peace, justice and wealth - not the destruction or domination of the former aggressor. Aggression need not lead to further aggression. Nor should not. This is accomplished by Karma Yoga, control and strength over action.