Writing in the Washington Post, former KGB officer Oleg Gordievsky, who defected to Britain in 1985, lays the blame for the Politkovskaya and Litvinenko killings squarely at the doorstep of the Kremlin's KGB:

The KGB and its predecessors liquidated people abroad quite regularly in the 1920s and '30s and even after World War II. But after two embarrassing and highly publicized defections of assassins, in 1957 and 1959, these activities ceased. Nikita Khrushchev, Leonid Brezhnev and later Yuri Andropov all avoided political killings when they led the Soviet Union.

(Of course, this did not prevent the assassination in London of Georgi Markov in 1978, when the Bulgarian dictator Todor Zhivkov persuaded Andropov to allow the KGB to help carry out such an operation.)

There were no secret assassinations under Mikhail Gorbachev or Boris Yeltsin. But under Vladimir Putin, the militant element of the KGB (now known as the FSB) slowly began working to persuade the leadership to carry out such killings, according to my sources. "Too many enemies," they said.

Those members of the FSB have a different style than in the past, however. The Communist Party was cruel, but it had its rules. The current people are like bandits -- no code, no rules, hard to distinguish from the Mafia. The gangster mentality started to spread after 2000; there were assassinations inside the country, of enemies of the regime. But there were so many contract killings at the time under Putin that it was difficult to tell which were the work of the FSB and which were not. In that atmosphere, it was easy to disguise an assassination.

The FSB has also become a protection racket. Some of those in business who are willing to go along with the FSB report everything to its operatives and also give 10 percent of their profits to the KGB's successor agency. And everyone is happy.

So in a way it's a big criminal state. The FSB has become like the Mafia in its methods and goals.

In 2003 the journalist and reformist politician Yuri Shchekochikhin was murdered in Russia. It was obvious from the way his "illness" developed that he was poisoned.

Anna Politkovskaya, a courageous journalist, honest and intelligent, was shot two months ago. Well before that -- in 2004 -- she was poisoned on a flight to the Caucasus. It was, I am certain, the work of the FSB. Afterward, the Putin-controlled media put out the usual propaganda to cover up the act. After Politkovskaya's death this year, many Russians said -- because she was Jewish and had American citizenship -- "Oh, just as well someone shot her; she was probably an American spy."

In July Russia's parliament passed a law, introduced by Putin, to permit the assassination of "enemies of the Russian regime" abroad. As a result, overeager -- perhaps chauvinistic, anti-Semitic or xenophobic -- factions within the FSB may suggest someone to kill. But there is no paper trail. (By the way, I don't think the recent illness of Yegor Gaidar -- a man whom nobody reads, whose importance is entirely in the past -- was due to poison. He is too insignificant to be killed by the regime.)

Here, too, the FSB has learned from the example of Joseph Stalin. Documents proving Stalin's atrocities continue to surface. To prevent such disclosures, orders for assassinations no longer have names or signatures on them, according to what I am told by my connections. Directives such as the one to assassinate Alexander Litvinenko are written to say, for example, "Request permission to carry out inquiry abroad," with no mention of the target. The document goes to an archive with nothing tying those involved to an assassination.

The first such killing took place three years ago, in Qatar. Zelimkhan Yandarbiyev, a former president of the Chechen republic, lived there as a pensioner, and was with his son and bodyguard when his car exploded. The two Russian intelligence agents who carried out the killing were caught, tried and imprisoned. But because Qatar wanted to avoid trouble with Russia, the prisoners were released to their home country after five months, to serve their sentences there. Once home, however, they were decorated rather than jailed.

Now, with Litvinenko, they have dared to kill a citizen of Britain on the soil of that country. Yandarbiyev, Shchekochikhin, Politkovskaya, Litvinenko: Russia has become a terrorist regime.