It is a mistake to consider hatred as something that should be avoided. To hate a particular individual is a waste of time. However, hate of a system, hate of an institution, hate of a policy, hate of ignorance, hate of lazyness, hate of greed, are all admirable things. Many people hate a group of people, (say muslims or israelis or catholics) because their culture or their system of beliefs, in the majority, reflect IDEAS and PRINCIPLES we hate. Rather than confront these ideas and principles with our hatred, and seek to eradicate them from existance, we instead seek to eradicate the people, as it is a much easier task to envision and accomplish.
That being said, it is not necessarily WRONG to hate a group of people, as long as that hatred is justified, backed up if you will, by explaining the principles or customs that that group (in general) exhibit that offends us. We should hate fundamental extremists of ALL religions because they are generally bigoted, sheep-like people that refuse to see any point of view or way of living that differs from their own. We should hate the aloof nature of many liberals, who preach from ivory towers about right and wrong, but have never soiled their hands in the trenches of the social war they so strongly advocate. We should hate a culture like that of the current Mexican governmental system because it is rife with corruption and lack of compassion regarding the welfare of their own people. However, rather than seeking to kill ALL religious fundamentalists, imprison ALL liberal dogmatiscists, and engage in genocide in Mexico, we should seek to rid those groups/people of the endorsement of ideals which we find offensive. It is in removing the ideals from these entities that we encounter difficulties, and where some individuals, refusing to part with ideas so dangerous to the welfare of other people, must be eliminated from having a voice to spread those ideas. But we as the persons doing the removal service should recognize that it is not the geographic place of birth, the DNA sequencing, or the manner of prayer that should make someone a candidate for such harsh action, it is the ideas and principles. Therefore when a society ceases to have offensive ideas and principles, we should cease to hate that society.
Some would ask the manner in which we should determine the method of measuring what should be offensive and what should be tolerated. This is simple. There are 2 conditions.
1)As long as the belief or custom harmes no one;
it should be tolerated.
2)Preservation of the whole of society should be considered before the protection of a minority.