Once Atlas Shrugged went to the top of Amazon's fiction bestseller list in February this year the liberals became worried. Rand's espousal of capitalism, and more to the point her delineation of the consequences of not espousing it, are deliberately extreme. She was not seeking to make a point with intellectuals: she had all but written them off. She was seeking to make her point with middle America and she wrote accordingly. Her novels were savaged by highbrow critics when they were published. The film of The Fountainhead - for which she also wrote the screenplay - has always been regarded as, at best, a curiosity, at worst as preposterous. Those who have never read a word she wrote - or have tried to read them, but have never progressed far beyond the opening chapters of any of the four novels (the other two being We The Living and Anthem) - glibly trot out the assertion that her prose is "turgid". It is anything but. In its Hollywood-style accessibility it may be vulgar, but it is fluent and her narratives have exceptional pace. Even at the focal point of Atlas Shrugged - the speech by John Galt over hijacked airwaves where he sets out his terms, and those of his confederates, for returning to America and participating in normal life once more, and which lasts for over three and a half hours in the unabridged audiobook of the title - she has a knack of maintaining that insistent tone that keeps the reader's attention for a surprisingly long time. Of course, it is structurally absurd: but by that stage in the book only the dedicated are still reading, and the words have taken on the aura of a religious text.

Rand knew what she was trying to do: she chose a popular form, storytelling, to transmit her ideas because she sought the maximum number of converts. Judging by the persistence of her influence, it worked. She identified a raw nerve in the American body: that which prizes freedom and "the American dream" above all else, and which fears the state as the only engine that could ever compromise that. In the period of uncertainty after the Second World War, the era of McCarthyism and the Cold War, she had a strong audience. At a time when America and her dream have been shaken and challenged as never since the 1930s, hers is a ready-made prescription that can be made to seem a prophecy. But does it only apply to America?