The incident, a classic Cold War tit-for-tat, may be related to something much less exciting than James Bond-style capers, namely visas.
Stanislav Borisovich Gusev, a second secretary in the Russian embassy in Washington, was allegedly caught outside the State Department with an eavesdropping device. He was detained by the FBI, then handed back to the Russians. Declared persona non grata, he has been ordered to leave the country within 10 days.
It was only last week that the Russians arrested Cheri Leberknight, a second secretary in the US embassy in Moscow, for espionage. She, too, was said to have had eavesdropping equipment for listening in to surveillance agents, as well as equipment to allow agents to communicate with US officers. She was reportedly on her way to a rendezvous, but as the location was marked on a map, it would seem she was no superspy.
US officials said that they had been watching the Russian for some time, which suggests that they picked their time carefully. A listening device was found in a "sensitive area" of the State Department, they said, on the seventh floor. No senior official had used the conference room involved for some time; it is likely both that the device was not in a high-security area and that America was waiting to use the device against the Russians.
In an unusual statement, the Russians clearly indicated they saw it as a tit-for-tat response. Boris Labusov, spokesman for Russia's Foreign Intelligence Service, said: "I think there is a certain sequence here. We think this detention and the further expulsion of the Russian diplomat from the United States can be regarded as a reaction of the American side to the latest events in Moscow connected with the detention and expulsion of an American diplomat. As far as the Russian side is concerned, we gave up the principle of an eye for an eye long ago."
The day before the Russians "lifted" Ms Leberknight, the US charged a navy codebreaker, Daniel King, with selling secrets to Russia. Both sides said that was unrelated.
What may be related is that America and Russia are currently tussling over the issue of visas for their intelligence officers to operate under diplomatic cover in each other's country. Many officers from both sides will be accredited, known to their host governments and in some cases co-operating openly with them. In July, the US asked the Russian national security adviser to cut back on the number of intelligence officers in Washington, claiming that the numbers had reached Cold War levels. That security adviser was Vladimir Putin, now Russia's Prime Minister.
It seems unlikely that this will be an end to the saga. The logical reaction for the Russians would be to up both the numbers and the seniority; first secretaries in the US embassy may soon be checking their luggage. But despite the growing problems in US-Russian relations over Chechnya, neither side wants a fundamental split.
The Russians may suspect that - for all its reluctance to let their people in - America has gone over the top in deploying its intelligence officers. In the last few years, other countries, including Germany, have complained at the number of Americans operating on their soil.