It ought to be a stale piece of agitprop. It isn’t, because the BBC’s drama department has emerged from its torpor and is now offering excellent productions, most notably War and Peace and the superb Happy Valley. For the dramatisation of The Night Manager, it hired a cast so good no script could defeat — Olivia Colman, Hugh Laurie, Tom Hollander and Tom Hiddleston — and found the novel’s strengths.

I can describe the faults of the ideology of the 21st century pseudo-Left: its lack of concern for the victims of dictatorship; its indulgence of clerical fascism; its occidentalist conviction that the West is the only enemy worth fighting. But le Carré is a novelist, not a political theorist. If you accept his premises, and after Tony Blair’s refusal to argue with Washington about Iraq they are easy to accept, you enter a convincing fictional world.

Le Carré has the vices of the old conservative British establishment, and not just in his Jew obsession. He resents the American empire usurping British power and leaving us as its poodle, and engages in a quasi-colonial denial of the autonomy of the peoples of the poor world. But he also has the old establishment’s virtues, most notably its ability to appeal to a vision of a better England which the Left can rarely match.

In The Night Manager, an honest spy realises how deeply the bribes of the illegal arms and drug traders have penetrated government and the City:

For Goodhew it was as if the very pageantry of England was dying before his eyes. Dragging himself homeward in the small hours, he would pause to stare feverishly and wonder whether the daily stories of police violence and corruption were true after all, not the invention of journalists and malcontents. Entering his club, he would spot an eminent banker or stockbroker of his acquaintance and instead of flapping a hand at them in a cheery greeting as he would have done three months ago — would study them from under lowered brows across the dining room, asking them in his mind: Are you another of them? Are you? Are you?

You may object that no one has spoken like this for 30 years (“the very pageantry of England”). But you cannot deny that it is well said. Asking if le Carré’s world is realistic is as pointless as asking if Middle Earth or Narnia is realistic. If you decide to cross its borders, it works.

The sadness of it all is that ever since the attempt to murder Salman Rushdie we have been engaged in intelligence and real wars. Yet as far as fiction is concerned, the enemy might as well not exist. Hundreds, probably thousands, of writers have taken le Carré’s road, and explained it away by describing the evils of the West and the cliques in the CIA and MI6. Whatever truths they utter, I cannot escape the feeling that they are cowards.

But what would happen to le Carré and the BBC if they took on more dangerous targets than MI6 and the CIA? They can deny that they self-censor all they want, but everyone knows they would be haunted by the fear that the heirs of the men who wanted to murder Rushdie might try to murder them too.