One major problem: He can't do it because the other G-8 nations won't let him.

  But the fact that he's proposing to try, risking a return to Cold War tensions with the world's second-largest nuclear power after 20 years of prickly partnership, raises questions about McCain's judgment. It also underscores that many of his top foreign-policy advisers are of the same neo-conservative school that promoted the war in Iraq, argue for a tougher stance toward Iran and are skeptical of negotiating with North Korea over its nuclear program.

  The Group of Eight, or G-8, as it's popularly known, makes decisions by consensus, so no single nation can kick out another. Most experts say the six other countries — Great Britain, France, Italy, Germany, Japan and Canada — would never agree to toss Russia, given their close economic ties to their neighbor. A senior U.S. official who deals with Russia policy said that even Moscow would have to approve of its own ouster, given how the G-8 works.

  "It's not even a theoretical discussion. It's an impossible discussion," said the senior official, who requested anonymity because he wasn't authorized to speak publicly. "It's just a dumb thing."

Aside from that, many wonder whether McCain's suggestion would be wise policy. They fear that if McCain is elected and follows through on an attempt to toss Russia from the group, it could anger and isolate Russia, which has been increasingly assertive on the world stage, autocratic within its borders and is the second-largest producer of the hydrocarbons that feed the world's energy needs.

  "In Europe, there's very little support ... for a policy like that," said Stephen Larrabee, an expert on Europe and Russia at the RAND think tank. "It's too late in the game to try and oust Russia."

  The proposal also seemed at odds with the theme of McCain's speech, which promised a less unilateral approach to world affairs than the Bush White House has pursued. That could reflect tension between two Republican foreign-policy camps vying for influence in McCain's campaign: the pragmatic realists and the hard-line neo-conservatives — with the neo-cons ascendant for now in Russia policy.

  "There are a lot of important issues that we need Russia's support on. ...What's to be gained by tossing Russia out? We feel more self-righteous about ourselves?" said Andrew Kuchins, the director of the Russia and Eurasia program at the Center for International and Strategic Studies, a center-right think tank.

  Randy Scheunemann, the foreign-policy director for McCain's campaign, acknowledged that "there would be very vigorous discussion" within the G-8 of a proposal to exclude Russia. But, he said, Russia was "on a different political and economic trajectory" when it joined the group a decade ago, and he said it's unlikely that the same invitation would be extended today.

  Scheunemann vigorously disputed that the proposal is a product of McCain's neo-con advisers. McCain's position on the issue dates to 2003, he said.

  The G-8 is an informal alliance of the world's leading industrialized democracies. Leaders gather annually to discuss a broad range of global issues, from the economy to security to the environment. Ministers from member governments then coordinate policies behind the scenes in accordance with decisions taken at the annual summits.

  The alliance was known for years as the G-7 until Russia was admitted in 1997, at the behest of the Clinton administration, as a way to encourage further democratic and economic reforms under President Boris Yeltsin.

  Russia has always been an odd fit for the group. While it's risen in recent years to join the ranks of the world's top 10 economies, that's due to its energy exports, not its modest industrial capacity. And its experiment with democracy has gone into reverse in recent years, which makes it doubly out of step with the seven industrial democracies.

  McCain's proposal addresses concerns about Russia's behavior, which became more adversarial under President Vladimir Putin (who, though he leaves office this month, will become prime minister and remain Russia's dominant figure). Examples include its meddling in the affairs of neighbors such as Ukraine and Georgia, its threat to aim missiles at other European neighbors in response to President Bush's plans for a Europe-based missile defense and its crackdown on political dissent.

  "It's not from left field," said Derek Chollet, a senior fellow at the Center for a New American Security, a bipartisan foreign-policy research institution. "As Russia has de-democratized, there's been this whole question of, `What do we do?' The title is industrialized democracies. If Russia is drifting away from democracy, what do we do with it?"

  But McCain's solution "on a scale of one to 10 of possible action, is going to 11," Chollet said.

  Instead, "you just have to be cold-hearted about this," said Colin Bradford, an expert in global governance at the Brookings Institution, a center-left Washington research center. "We all believe in human rights and democracy. ...But it doesn't matter what the internal regime looks like. You need them at the table. We've got to figure out the incentives" that will make Russia behave better.

  Some agree with McCain's approach.

  Ariel Cohen, a senior research fellow at the conservative Heritage Foundation, said McCain's proposal was "right on the money."

  "It sends Russia a strong message to stop behaving the way it does," Cohen said. "As long as Russia doesn't behave like a democracy, why should it be in the G-8?"

  Cohen added that there are plenty of other forums for Russia to be heard in the world, including bilateral talks, the United Nations and the Organization for Security and Cooperation in Europe.

  McCain clearly dislikes Putin. A line he likes to use on the campaign trail is that while Bush looked into Putin's eyes and saw his soul, McCain looked into Putin's eyes and "saw three letters: KGB." Putin was a longtime officer in the Soviet intelligence service.

  The feeling appears mutual: McCain and campaign pal Sen. Joseph Lieberman, an independent Democrat from Connecticut, regaled reporters a few months ago with a story of the conference in Munich, Germany, "where Putin last year chose to give his first real strong anti-American speech ...when you saw a real change," McCain said.

  "He looked over and glared at me and Joe in the front row a couple of times."

  That may be because McCain and Lieberman had sponsored a bill in 2005 urging what McCain is proposing anew: that Russia's G-8 membership be suspended.

  What's striking about McCain's proposal is how far it is from the Bush administration's long effort to engage Putin. Democratic presidential candidates Hillary Clinton and Barack Obama also have offered tough rhetoric on Russia.

  Of course, Kuchins said, "they're all on the campaign trail. Bush has to actually govern."