I believe this quote is what reveals the evil of Ayn Rand.
What has happened, historically, when a person, or group of people, have been in power and they are guided by the belief that they and only they who have exactly the same beliefs (political or religious)? How do people behave when they take no notice of the plight/arguments of the "other side"?
I was "into" Ayn Rand during college; I voted for Ron Paul in 1988; I tagged along with the "Objectivist Club" at UVa for a while. It was when I read the book of essays "the virtue of selfishness" and in particular the essay "The growing cult of moral greyness," I decided it was not logical.
For all distinctions ("atmosphere" vs. "space" for example) there are areas where you are clearly in one or the other, but there is a zone in which you are in both/neither. This is true for all physical distinctions and all political distinctions.
To go into a tricky middle-ground, and to emerge in favor of one side, disregarding the other, you have to invent logical pedestals to support the conclusion you wanted in the first place (consider Pluto, for example; how did it become not-a-planet?) I saw this happening all over Ayn's work.
I forgot where, but she said that if you come across an issue where there does not seem to be a right and wrong, then you do not know enough about it; after filling in the details, and analyzing things properly, you will always be able to determine which side is right (I'm paraphrasing out the wazzoo! Feel free to correct that one; I might be recalling lecture notes here; but it's part of that philosophy nonetheless)