Who is Ayn Rand? The answer is critical to understanding Atlas Shrugged, the libertarian blockbuster written by this Russian-American author. A book of big ideas first published in 1957, it is selling strongly again. Its depiction of a US enervated by interventionism has struck a chord as Washington spends billions on bailing out banks and businesses.

The literary device that underpins a plot Wagner would have considered over-elaborate is the question: “Who is John Galt?” It is uttered by despairing Americans whose country is collapsing into chaos. Socialist politicians, venal scientists and corrupt businessmen are all to blame.

Galt, it transpires, is a brilliant engineer who has organised a “strike” of the US’s most talented businessmen. These are the “Atlases” who shrug off the world supported on their under-appreciated shoulders. This precipitates anarchy and the remaking of society along libertarian lines.

So who is, or rather was, Ayn Rand? Born Alisa Rosenbaum in St Petersburg in 1905, she saw her father’s pharmacy confiscated by the Bolsheviks in 1917. She studied Nietzsche before fleeing communist thuggery to the US. She scraped through the Great Depression reading scripts for Hollywood director Cecil B. DeMille.

No surprise, then, that Atlas Shrugged is epic, melodramatic and hostile to collectivism. It expressed the disquiet many Americans felt as state control spread during the Depression and the second world war, along with 1950s fears of communism and nuclear destruction.

The book is back in fashion. The Ayn Rand Institute in California says twice as many copies were sold in the US in 2008 as in 2007, and three times as many in the first seven weeks of 2009 alone. It is popular with business people, usually portrayed as creeps by novelists. They are mostly heroes in Atlas Shrugged, whose publisher, Penguin, is a sister company to the Financial Times. The premise that free trade should rule relationships in place of guilt and coercion appeals to them.

Left-leaning liberals mostly hate the book. European sales are apparently modest. There is little place for the weak or for compassion in Rand’s world.

But few critics have picked up on the trail of evidence that implicates the author, who died in 1982, in the current economic cataclysm. Rand popularised the libertarian economic ideas that found political expression through Margaret Thatcher, former UK prime minister, and Ronald Reagan, former US president and a Rand fan. Alan Greenspan, who as US Federal Reserve chairman pumped up credit in the wake of “dotbomb” and fuelled the subprime crisis, was also an admirer.

Many commentators blame the laisser faire ideology that Rand and others espoused for triggering the credit crunch. State intervention has been a response to disaster rather than triggering it in the way depicted in Atlas Shrugged. An answer to “Who is Ayn Rand?” is therefore: “One of the accused.”

The writer is an FT columnist