For anyone who spent time in the old U.S.S.R., the spat between London and Moscow over the extradition of Andrei Lugovoi, a suspect in the murder-by-radioactivity of Alexander Litvinenko, has a distinctly familiar air. Britain believes it may be after a killer who condemned Mr. Litvinenko to a horrible death and endangered untold numbers of others with radiation. The Kremlin sees a West out to get Russia.

It responds with all the familiar snarls and threats: «pure foolishness,» barks Vladimir Putin; «provocative actions,» and «most serious consequences,» echo his minions. And Britain dutifully plays its cold-war part, threatening to expel Soviet — whoops! — Russian diplomats.

All that’s missing is Tass darkly asking, «In whose interest is this hullabaloo?»

Flashbacks like this provide plenty of ammunition for those who argue that Mr. Putin is dragging Russia back into the old Soviet swamp.

But then there’s that other Vladimir, the one who goes fishing with the Bushes, father and son, in Kennebunkport and chums it up with Angela Merkel at the G-8 summit in Heiligendamm. Then just when everyone’s taking a second look, poof! He’s the Cold Warrior again, blasting American unilateralism, suspending Russia’s participation in the treaty on conventional forces in Europe, blocking independence for Kosovo.

Mr. Putin mirrors the contradictions, aspirations and insecurities of his country. In the view of a large majority of Russians, he has restored order and national pride after all the chaos and humiliations of the first post-communist years when Russia suffered an economic setback worse than America’s Great Depression, the plunder of national assets by a handful of oligarchs, political chaos and a nasty war in Chechnya.

That was also a time when Russians went from admiring the United States to resenting it, and not without cause. For all the moralizing about peace and democracy, the United States, and the West in general, made no effort to help Russia when it was down and instead seized the moment to expand NATO up to its borders and in many ways treated Russia as a defeated enemy.

The American invasion of Iraq and Washington’s plans to install a missile defense system near Russia’s borders extinguished whatever lingering allure America held.

So for the Russians, it’s payback time — in Kosovo, in Europe, in Iran, wherever Mr. Putin can tweak America’s tail. It certainly plays well in Pskov: Mr. Putin’s popularity has never dipped below 70 percent.

But Mr. Putin also represents a real — albeit selective — authoritarian drift, and a clear nostalgia for lost empire. He was, after all, a KGB agent, a breed trained to see the glitter of the West as eyewash, to look everywhere for threats and not to reveal much about themselves.

The slogans of Mr. Putin’s administration — ukrepleniye gosudarstva (strengthening the state) and upravlyayemaya demokratiya (managed democracy) — have that old KGB flavor. In true Soviet tradition, Mr. Putin has given no quarter to opposition politicians, defiant oligarchs or independent television newsmen, and he seems incapable of perceiving Ukraine, or Georgia, or most other former components of the Soviet empire, as sovereign states.

For all that, Mr. Putin’s Russia is not the Soviet Union, and most Russians don’t see what’s happening in quite black-and-white terms. It’s a far freer place than it was two decades ago: The Internet is still unfettered; newspapers are cautious but lively; intellectual life is thriving; Russians and foreigners come and go freely; and private capital still reigns, for all the well-publicized government seizures in the energy sector.

Russia is still a work in progress, and it is too early to predict which way it will go when — or if — a new president replaces Mr. Putin next year. Meanwhile, the West, which needs Russia’s energy, and Russia’s help in dealing with Iran, Kosovo, North Korea and climate change, needs to discard its own cold war stereotypes and start treating Russia as a potentially constructive partner.

That would be a lot easier if Mr. Putin would put that Soviet mask away for good — and let Mr. Lugovoi stand trial in London.