And in that case you cannot respect those opinions?
Look at gay marriage. There are large percentages of people in the US who would like to return to a time when gay marriage was illegal. If you were married to a same sex spouse, do you think you'd be able to say "oh, that's OK, I respect your difference of opinion." No, you'd do everything in your power to protect your family from being attacked.
I mean, just imagine how straight people would react if the government tried to invalidate their marriages.
I thought the parent comment suggested that the opinions of those who cannot separate out their beliefs from themselves, so when you question their opinions, they feel you are attacking them personally, are less respectable.
At some point you need to draw a line.
I believe the fundamental dichotomy is that, for some of us, our opinions are not who we are. We can change our opinions and remain the same people.
For others, their opinions ARE who they are. They cannot separate out their beliefs from themselves, so when you question their opinions, they feel you are attacking them personally.