Rupert Cornwell: Whatever happened to the idea of honour among spies?

'Whatever you think of Kim Philby or Donald Maclean, they were not in it for the money'

For a moment last Friday, a familiar old frisson briefly passed through Washington, the uncontested espionage capital of the world. A suspected spy, with links to a top secret US intelligence gathering agency, had been picked up as he was about to board a flight for Europe and charged with passing information to a foreign power.

Then, just as quickly, disappointment set in. The suspect was not a diplomat or high official but a retired air force staff sergeant. The one foreign country named in the affair thus far is not Russia but Libya. This disclosure will feed paranoia about "rogue states", but does not promise a stirring contest between equals. The sad truth is that, while spying matters as much, perhaps more, than it ever did, the second oldest profession just ain't what it used to be. Once it was part of the struggle between ideologies and competing global systems. These days, all that matters is money.

We do not yet know exactly how serious is the case of Brian Regan, the retired US air force sergeant and intelligence analyst. But he has much in common with America's two most recent spies of note, the CIA mole Aldrich Ames and the FBI agent Robert Hanssen. Like them, he is a creature of the tranquil middle-class Washington suburbs. And when you strip away the embitterment, the office emnities and frustrations that undoubtedly played a role in such cases, there is one ever-present motive: money.

The Russians paid Ames $2.7m (£1.9m), supporting a lifestyle which a mid-ranking CIA officer could never remotely afford. They rewarded Hanssen with $1.4m in cash and diamonds. Still unclear is how much Mr Regan was to receive for hawking his wares, which came with the impeccable quality stamp of the National Reconnaissance Office (NRO), the US Government's top-secret satellite agency where he had worked for the past 12 months. We do know, however, he was carrying $53,000 of consumer debt, which must have been close on a year's salary.

How squalid compared with the old days. Whatever you think of Kim Philby, Donald Maclean or George Blake, they were never in it for the money. However misguidedly, they believed in the superiority and rightness of the communist cause. Their main recompense, apart from the thrill of fooling their employers, was the knowledge that if they had to flee, they were assured as decent a life behind the Iron Curtain as socialism could provide. Such was the KGB's code of honour in dealing with its foreign operatives.

The West behaved similarly with its recruits. Take Oleg Penkovsky, the colonel in Soviet military intelligence and the most important Cold War spy of all. His consolation was the promise of safe haven in the West. Nothing gave him more pleasure than to have himself photographed, as a self-described "soldier of the free world", wearing British and American service uniforms during small-hours meetings with his Western handlers in the Mount Royal Hotel, when he visited London as a member of a Soviet trade mission in 1961.

True, Hanssen is said to have been smitten with the mole bug as a young man, when he read about the exploits of Philby. Certainly his craft was excellent (he never revealed his name to his Russian handlers) and he shared the maestro's knack of concealment. Until too late, we could not believe that Philby, archetypal product of privilege and the English establishment, could be a spy. In an all-American context, Hanssen was the same. Outwardly he was an exemplary family man, liked by the neighbours, attending mass each Sunday, somehow making ends meet to raise six children and send them to college. In fact he was the most dangerous turncoat in the history of the FBI.

But with this common gift for dissembling, the similarities between the old and the new spies end. Espionage these days is a lopsided business between unequal parties in which, strangely, the dominant party is disproportionately vulnerable.

America has the technology and the secrets other people want and are prepared to pay big money for. In American sporting parlance, it's playing defence. This imbalance also explains why Russia probably has more spies in the field now than it did at the height of the Cold War. Today's targets are less military secrets than commercial and industrial information.

The French and others may go on about Echelon, the wicked American-led conspiracy of the English-speaking powers which supposedly vacuums up Europe's industrial secrets. In truth, the priority of the CIA and the FBI is not so much to obtain other people's secrets as protecting America's own. The name of this game is not intelligence but counter-intelligence – in other words, finding out the names of the other side's bad guys, especially the bad guys who are supposed to be on your side. They are the Ameses and the Hanssens of this world; people with that dangerous combination of a bad attitude, secrets to sell and maxed-out credit cards.

The signs are that America, not before time, is getting better at this. The Ames investigation was a fiasco, taking the best part of a decade despite clues to the identity the mole that even an Inspector Clouseau wouldn't have missed. The case against Hanssen was far trickier and took several years to crack – thanks, ultimately, to the cultivation of a source in Moscow who turned over to the Americans Russian intelligence's file on the still anonymous Hanssens. Mr Regan's alleged offences, by contrast, only started in the summer of 2000, when he retired from the Air Force to start a new job as a contract employee for the NRO.

The paradox is, however, that the unmatched superiority of the US makes spying arguably more important than ever. For in the long sweep of history, which spies from espionage's vintage era of the Cold War will be judged to have really made a difference? Penkovsky certainly, because the information he provided about Soviet nuclear capacities enabled President Kennedy to face down Khrushchev in the Cuban missile crisis. The atom spies too (among them Maclean but not Philby) who speeded Stalin's development of the bomb.

But for the most part espionage during the Cold War was a game played by two roughly equal sides, whose efforts often cancelled each other out.

Not so today. If America's foes are ever to level the technological and information playing field, spying offers one of the few available avenues. The Regan case, whatever its outcome, is proof we are living a new age of spying. Not a golden age however. In this one, the coinage is 30 grimy pieces of silver.