There have been a number of threats to Russia's security in recent years, from Chechen terrorism to the country's worrying demographic decline. But according to sources close to the Russian security services, what the authorities fear most in these times of economic crisis is the very thing that many Russians see as the country's saviour – nationalism.
Amid a dizzying array of May Day marches, featuring various groups from across the political spectrum, all eyes were on the nationalists. They gathered around a metro station in north Moscow, as well as in other cities across the country, calling for all immigrants to be deported and a "Russia for the Russians". In the event, the Moscow meeting passed off peacefully; police arrested a few demonstrators for the possession of knives, and the rest dispersed without incident. But with a huge migrant population, poverty and unemployment among locals, and with the high oil prices that fuelled the economic boom of the past few years a fast-receding memory, many feel the time for Russia's nationalists to take the political initiative is coming soon.
Then there's Alexander Belov, Moscow's answer to the BNP's Nick Griffin. Dressed in a sharp black suit, the light of a Bluetooth receptor constantly winking over his left ear, he fingers a set of Orthodox Christian prayer beads and sips a freshly squeezed orange juice, looking like one of the thousands of well-to-do businessmen who have made decent money as Russia boomed over the past decade. But as well as being successful in the construction industry, Mr Belov is also Russia's most famous racist. He believes that the time for the nationalists to take the limelight is coming soon.
"What I want is very simple," he says, in a quiet and measured voice. "I don't want parts of Moscow to be ghettos. This city is already full of places where Russians aren't welcome, and it's unacceptable. This is a Russian city and should remain that way."
An erudite and self-assured man who heads a group of skinheads with a reputation for violence, he leads the Movement Against Illegal Immigration – the DPNI, as it's known by its Russian initials – one of Russia's largest far-right groups. One of its main policies is that Russia should introduce a visa regime for migrants from the former Soviet republics, sending most of the millions of Gastarbeiters (Russians use the German term to refer to guest-workers) back home.