Hatred, like all other emotions (including love), cannot be separated from the thoughts that underlie it. For example, my hatred for Hitler is a result of my knowledge of what happened during the Holocaust, and my evaluation of those events; my hatred for Osama bin Laden is a result of my knowledge of what he caused to happen on 9/11, and my evaluation of those events.
Without the knowledge, the hatred would be non-existent; with the knowledge and the evaluation, the hatred is inescapable - provided I don’t counteract that knowledge with mollifying beliefs, a coping mechanism that many people use.
An irrational hatred is also based on our beliefs. A person could not feel racial hatred unless he had the **belief **that people of some races are inferior. And a person could not feel homophobia without the **belief **that gay people and/or gay sex are bad. This is why I consider people to be racist or homophobic, based on their beliefs, regardless or their professed feelings and actions.
We can’t simply turn our emotions on or off without first making an adjustment in our thinking, and our emotions can be an extremely valuable indication of exactly what that thinking (or lack thereof) really is. From a psychological point of view, it is very self-destructive to deny oneself certain feelings, because you think they’re “wrong” or “inappropriate.” For how many centuries have people screwed themselves up by thinking that “real men” or “good girls” weren’t supposed to feel certain types of emotions? The only way we have learned to validate those feelings has been to change our way of thinking. Sadly, many people haven’t even begun that process.