There are people...actual humans...who are called "it" all the time, and no one even blinks. In fact, I've heard the word used from two totally different places.
1) The word "it" is used to reference a baby yet to be born. When one is asking the question of "Are you going to find out if it's a boy or a girl?" In this instance, the word "It" is used as a pronoun because of the uncertainty factor. It is not used in a disparaging way
2) The word "it" is used to help justify an abortion, or the Holocaust, or ethnic cleansing, or any other situation where a person is "dehumanized" in order to make their death more justifiable to the individual or group.
In both instances, the word is used in reference to another person, however the intent behind the usage characterizes it dramatically different.
~Jeordam