The spies we cannot forget

Hitherto they have been labelled sordid traitors, but the BBC drama, due to hit our screens next month, treats them so sympathetically that one Russian defector, Oleg Gordievsky, says it might as well have been made in Moscow.

The problem is that the Cambridge spies were glamorous. They led extraordinarily adventurous lives and took part in momentous historical events. They sacrificed family, friends and country for a political ideal and died unrepentant before it all collapsed. They were wrong, but in their lifetime they stuck to their youthful, idealistic commitment through thick and thin. Not many of us can say that.

In 1988 I spent a week with Kim Philby in Moscow, where he lived after fleeing in 1963 from the vengeance of the British Secret Intelligence Service. I had conversations and correspondence with Anthony Blunt and two of Philby's four wives. I have written a book on Philby, Burgess and Maclean, and a separate book on Philby.

With this background I can say that the BBC drama is not history. It compresses events, invents others, plays with chronology and puts fictional words into the mouths of the main characters. This is the playwright's privilege. It largely ignores the victims of the spies' treachery - although as Philby told me, "It was a war and people die in wars". But it does not glamorise them beyond reason.

Everyone envies a risk-taker, especially in support of a cause, and these four young friends were not only risk-takers extraordinaire but absolutely devoted to their cause. "I had already decided at 19, after a good look around me, that the rich had had it too damned good for too damned long and that the poor had had it too damned bad and it was time that it was all changed." This is not a line put into the mouth of Toby Stephens, the actor who plays Kim Philby. It is Philby himself, in exile in Moscow in the twilight of his life, looking back on his decision to betray his country and explaining to me what he did and why.

Philby was right that change was needed and it did come after the war. But there was a lot to be disgusted about in Britain in the 1930s - one and a half million unemployed, the Jarrow hunger marchers, the snobbery, the casual anti-Semitism of everyday English life, Fascism on the rise in Germany while the pillars of British society trooped to Nuremberg to hobnob with the Nazis.

Can it be so hard to understand, as the BBC drama sets out, that intelligent, idealistic young men in their early twenties felt an urgent need to do something about the way their world was heading?

As we know, they turned to Communism. "The democratic socialists were unimpressive," Philby said. "They seemed to fold at critical moments. But all the time there was this solid basis of the Left, the Soviet Union. We felt it should be kept there at all costs."

Many others at Cambridge - and Oxford, too - would have taken the same path as Philby and his friends had they been given the opportunity. I think it is understandable and forgivable that the Cambridge spies made the commitment they did, when they did. What many find unforgivable is how they were able to maintain that commitment when the horrors of Stalin's rule became apparent. In particular, how could they remain loyal to Moscow after the Hitler-Stalin pact of 1939?

The answer is that they did not. They were as appalled and confused as the rest of the Western Left. Recently released KGB files on the Cambridge ring show their disillusionment and anger. Philby was working as The Times war correspondent with the British Expeditionary Force in France. But he was also spying for the Soviet Union.

He demanded of his KGB controller, "What's going to happen to the single front against Fascism now?" The KGB files do not reveal what answer his controller gave but it must have been unsatisfactory because in December 1939, Philby stopped working for the KGB and vanished. He only started work again when it was clear to him that war between Germany and the Soviet Union was imminent (Germany invaded in June 1941) and he could resume the anti-Fascist fight with a clear conscience.

Did none of the ring notice the frequency with which their controllers changed, and wonder what happened to them when they returned to Moscow? The answer is that they were all shot as suspected German spies, victims of Stalin's slaughterhouse of 1937-39.

I doubt that anything they might have learned about what horrors Stalin was inflicting on the Soviet Union would have made any real difference to their commitment. They were in too deep. Philby told me that when it became clear that "things were going wrong in the Soviet Union" his choices were limited.

Maclean felt the same. In Moscow, where he fled in 1951, he spent a lot of his time writing to Soviet leaders complaining about the way they were treating dissidents and he gave part of his salary to a fund to help their families while they were in prison. Just before his death in 1983, he wrote, "I'm still committed to the idea of each for all and all for each which gives socialism its moral leverage."

Burgess is the only one who may have regretted how his life turned out. He was too much the Englishman to be content in Moscow - he had gone with Maclean - and Alan Bennett's perceptive play, An Englishman Abroad, gave an accurate picture of Burgess's years in exile before his death in 1963.

Blunt changed in later years as his career as an art historian and Keeper of the Queen's pictures blossomed. It was his failure to honour his agreement with MI5 to reveal all and "name names" after he was granted immunity from prosecution and secrecy in 1963 that made the service decide in 1979 - with Mrs Thatcher's assistance - to "out" and destroy him.

The fascination the Cambridge spy ring has for us 50 years on is undiminished. Why? Because whether we find them glamorous or detestable, they force us to examine our attitudes to patriotism, treachery, class and political conviction.

They make us think about the duty of the citizen to the State and wonder if we too, given the right circumstances, could be traitors.

• Phillip Knightley is the author of Philby: The Life and Views of the KGB Masterspy.