I know who killed Alexander Litvinenko; it was the KGB, at least in spirit. For me, as for nearly everyone brought up under the Soviet Union, the KGB meant far more than the intelligence arm of the Communist Party.
When the so-called Russian oligarchs started getting seriously rich in the early 1990s, the first thing they did was to recruit former KGB personnel, from bodyguards and enforcers to eavesdropping specialists.
Vladimir Gusinsky, the liberal founder of the NTV television channel, caused quite a stir when he made Filipp Bobkov, former chief of the KGB's anti-dissident Fifth Directorate, one of his directors. Mikhail Khodorkovsky, proprietor of the Yukos oil giant at that time, chose the KGB rising star and analyst Aleksei Kandaurov as one of his sidekicks.
Boris Berezovsky, now exiled in the UK, was surrounded by KGB officers and was himself at the top of the intelligence apparatus during his time as deputy secretary of Russia's security council. One of his protégés was a young KGB colonel called Vladimir Putin. Berezovsky claims he proposed Putin to Boris Yeltsin as his successor; he thought his KGB background would come in handy.
The oligarchs needed the expertise and the skills of the KGB. But it soon became clear they needed something more: the psychological comfort of having this omnipotent institution accept them as the new masters. Most of the oligarchs were Jewish. All their lives the KGB had been out of bounds - Soviet security organisations did not employ Jews, and saw them as potential traitors. These complexes extended further. Most of the Soviet intelligentsia held the KGB in great awe. A mix of hate and admiration had been engraved on successive generations. It would decide whether you could get a good job or go abroad or live in a privileged city. Or it could decide to destroy you, to do away with you.
It wasn't just westerners who believed that the new capitalist Russia would become a "normal country", another Britain or France or Germany, not without its peculiarities, but essentially democratic. Many Russians also harboured those hopes. Russia today is richer and far more open than the Soviet Union ever was. But minds take longer to change than economic or political systems. When riches abound and minds remain in the past, then corruption takes hold.
Western economists proclaim the strength of any democratic society is its middle class. The maxim is supposed to apply to Russia, and you wouldn't dispute it watching the flashy foreign cars whisk past in central Moscow. The problem is that most of the owners can hardly afford them on officially declared earnings.
Not only do most people not pay full taxes, but in most cases the source of their wealth is graft. Bribery has penetrated every level of power and, according to the prosecutor general, its volume is comparable to the entire state budget. According to an independent think-tank, more than $300bn a year changes hands illegally - an average single bribe is now believed to be worth $130,000.
Late last month, President Putin gathered high-ranking government officials and pleaded with them "to learn to separate money and civil service". The audience in the packed Kremlin hall looked away in embarrassment, or maybe they were just checking the time on their expensive Swiss watches.
The people, meanwhile, are so busy doing deals that the roll-back of political freedoms has gone largely unnoticed. Few seem to care that parliament and local authorities have lost most of their power or that TV channels are, to greater or lesser degrees, all controlled by the state.
Some might complain that news programmes have become as boring as they were in Soviet times, but they are reassured by a steady flow of soap operas and pop concerts that were not available in the old days. Most Russians remain indifferent to the many contract killings of those who dare to challenge corruption, such as the Central Bank deputy director Andrei Kozlov, or those who irritate the authorities - the journalist Anna Politkovskaya, for example, or Litvinenko himself.
As for the oligarchs, they soon fell foul of a system they helped to create. Gusinsky was not saved by Bobkov. He had to flee the country. Khodorkovsky was sent to jail. Having been more directly part of the KGB himself than any other tycoon, Berezovsky was grateful to receive asylum in the UK.
The KGB came to be a state of mind. Never trust anyone outside your immediate family. Don't believe in anything but raw power. Expect everyone to be driven by base motives. Long after the collapse of Soviet communism, it lives on. It has become fashionable to suggest that the Litvinenko affair marks the start of a new cold war. The reality, however, could be more disturbing. Then you could raise the Iron Curtain and know who your enemy was. Now you are dependent on Russia as a partner in the so-called "war on terror" and as your major supplier of natural gas and oil. London's real-estate market is addicted to Russian money and Chelsea will never be the same after Roman Abramovich.
One of Russia's national dailies wrote this past week that Russians should be told not to settle their scores from back home, to leave Britain alone. You may as well ask the current gales to stop bashing British shores. No, Russia is here to stay; it is on your doorstep.
Andrei Ostalski is editor of the BBC Russian Service and author of "The English Rules" (Vremya)