Let's start with what I like about Atlas Shrugged. I liked Rand's clear focus on doing excellent work, of using your brain and persisting. I do agree with her main point that the need of the less competent does not entail a legal obligation to subsidize them on the more competent. I agree that society is best served by greater freedom, personal reward for work, private property, and a free market. I thought her description of the factory destroyed by egalitarianism was the best section of the book. I liked the railroad bits, too.
My fundamental disagreement with Ayn Rand, though, is in her notion that some people are naturally smart, rational, creative, and hardworking, and the rest of us are dependent parasites. Of course I accept that some people are smarter, more rational, more creative, and harder working than others. I think there is an element of nature in each of these qualities of a person, in descending order. But the role of nature is limited - let's say nature is only half of the story. In particular, I think how hard working people are depends more on social structure than on innate qualities. More importantly, I think smart, creative ideas come from unexpected people and unexpected places all the time. Rand is as much of a determinist as the harshest Marxist, and is equally wrong.
Second, while I agree that the need of the less competent does not entail a legal obligation to subsidize them on the more competent, it is still virtuous to help those in need. It is a personal virtue to be charitable. It is socially prudent to build up the basic competence of everyone and to build a social safety net to keep the most dependent from death and true misery. And this social safety net is prudent even for people who brought most of their problems on themselves. It is a virtue to care for the dependent because they need it; it is prudent to care for the dependent because "there, but for the grace of God, go I." Taking care of yourself as much as possible is a social virtue. Selfishness is not. Rand's philosophy owes the most, I think, to this part of Nietzsche's attack on Christianity, and is the ugliest part of her thought.
Which brings us to the wild unreality of the world she depicts. The main problem with her utopia, like all libertarian fantasies, is that it only works for self-sufficient individuals. That means no sick people, no disabled people, no very old people, and no children. A utopia without a place for children is absurd. The only positively depicted children in the whole story are the small sons of a woman in Rand's Atlantis who has made a vocation of motherhood ("not like the lies they teach children in schools."). In theory, everyone in this Atlantis has taken a personal oath to live only for him- or herself and no one else. Yet a vocation of motherhood makes no sense on those terms, and it is impossible for little kids to be part of a community requiring such an individual oath.
So we get to the unrealistic elements of Rand's telling of the story. Her characters have sex with each other because the Other represents their own highest ideal. This is certainly a better ideal of what sex is for than merely for sensual pleasure. Yet this ideal seems to have no place for marriage, and no place for children. A sex ideal with no place for children is retarded.
I am OK with an author making the hero in his or her own idealized image, but did Ayn Rand have to make Dagny Taggert not just beautiful and smart and eternally slender, but the only woman in the world worthy of the love (and sex) of not one, but the three greatest men in the world, in succession, each yielding graciously to the greater man?
Moreover, this novel is set in America, but this is an America with no religions, no ethnicities, no regions. The government has no political parties, no president, no real legislature, no politics; they are all just "looters." This is not really an American novel at all, but a vast Russian novel, with a (secular) Russian's sense of how a nation works.
I have met several people who read Atlas Shrugged as teenagers, especially those a decade or two older than me. Some were exhilarated by the sense that many bookish adolescents get when intelligence is defended against stupidity. Rationalism, and libertarianism generally, are the special province of independent young people who have no dependents and can't imagine that they themselves will ever need to depend on others. Most of them moderate their views when they marry and have kids, or when they or someone they love gets sick or old. Still, the old sense that the world would be better if the smart people like me were free of the stupid can be revived at a touch. It makes one feel like Atlas, carrying the world of the stupid. Which one might be tempted to shrug off.