sarai,
I agree with your statement:
Sexual orientation is obviously not a prerequisite for positive, competent and loving parenting....
Sometimes when we feel strongly about something but can't really articulate the reasons, it's because it was part of our upbringing, such as religious upbringing. For certain issues, we are preassured to just "believe" and not question. I think racial prejudices are past from generation to generation in a similar fashion.
I've been reading the biography of Teddy Roosevelt and something that really struck me was the prevalence of lynchings in the south (early 1900s)... something like one every few days. And that if someone spoke out about these lynchings, it was met with self righteous indignation from the southerners.
Sara
"I never give them hell. I just tell the truth and they think it's hell." - Harry Truman