First, I'd be interested in knowing how/why trying to raise one's children with similar politics and religion would be unfair? To whom?
Second, I'll play nice and answer you question.
If you believe your political and/or religious positions are well grounded and so lead to a better life in general it is unfair NOT to share that with your children. Its almost like wondering if its fair to teach your kids how to hunt and build fires if you live out in the woods. Sure they might pick it up, but if you have a skill (a form of knowledge) which provides an advantage then your better off getting that across to them early, so they can pick up more things to add to that knowledge base.
Essentially children are an extension of your own life and it only makes sense to pass on the results of your learning. Of course hardcore indoctrination and hoping you can stick them in a tight box forever would be unrealistic. Not sure if I'd say "unfair", but its a waste of time and leads to much suffering on both sides.
One thing I should probably add is that I believe child rearing without including politics/religion is self-defeating. Not only does it rob them of the benefits of one's own experiences, which means they have to reinvent the wheel, it assumes that they are somehow just going to learn about this stuff on their own and come up with an individual view point. I mean I assume the concept of "unfair" is coming from an idea that parents will smother a child's freedom to learn for themselves and develop their individuality.
It seems to me that in not teaching them your own political and religious views, you simply empower a lot of other people whose main interest is to teach your children what their political and religious outlook should be.
Edited by holmes, : typo
holmes {in temp decloak from lurker mode}
"What a fool believes he sees, no wise man has the power to reason away." (D.Bros)