Georgia, while not yet a NATO member, is pushing for early entrance despite Russia's strong objections.
The Russian incursion in August raises questions for newer NATO members - like the three Baltic states that were part of the Soviet Union before the fall of the communist empire in 1991 - about whether and how NATO would respond in the event that Russia chose to invade their territory.
That issue formed a part of the backdrop to a meeting here Friday of allied defense ministers who are divided over how to treat their relationship with Russia and how to proceed with NATO military reforms.
Meanwhile, U.S. Defense Secretary Robert Gates said Friday at the meeting's conclusion that he notified the allies that they will be expected to share the cost of a planned expansion of the Afghan national army.
"I let a number of my colleagues know that we would be in touch in terms of the importance of sharing the cost of the increased size of the Afghan army because, after all, the effectiveness of the Afghan security forces - and in particular the army - in the long term is NATO's exit strategy," he said.
The Afghan army is to grow from the current 80,000 soldiers to 134,000 as part of a strategy for building a security force that eventually can stand on its own to prevent the country from again becoming a haven for terrorists.
British Defense Secretary Des Browne said Friday that that although NATO has shown a "unity of purpose" in response to the Russian incursion into Georgia, the alliance has fallen into "bad habits" with regard to adapting its collective military forces to the challenges of warfare in the 21st century.
"We are lacking sufficient capabilities in key areas," like airlift, that would make the armed forces of each NATO member more useful beyond its own borders, Browne said, adding that Friday's talks were meant to produce progress toward important decisions by NATO government leaders next April.
Britain, among other NATO countries, has publicly backed Georgia.
"We have been able to say to him that we are in full support of the territorial integrity of Georgia," Prime Minister Gordon Brown said Friday following talks with Georgian Prime Minister Vladimir Gurgenidze. "We will be giving financial and economic support to Georgia and urging other countries to do so."
Before the start of Friday's NATO talks, Brown told Gurgenidze that Britain fully supports Georgia's aspiration to join NATO, said Brown's spokesman, Michael Ellam.
Gurgenidze told reporters he welcomes backing from Europe. "This is very important for Georgia at this time, as Georgia faces the existential crossroads of either staying the course as a young liberal European democracy with a vibrant market economy, or degenerating into something weighed down by its Soviet past," he said.
Gates, who was a specialist in Soviet affairs during his career at the CIA, said Thursday that while the crisis in Georgia has caused concerns within NATO, he does not believe the alliance faces the likelihood of war with Russia.
Gates, speaking with reporters in advance of a NATO defense ministers meeting, said there is a sharp division of opinion over what the Russian war with Georgia means for the alliance and its relations with Moscow.
"I think we need to proceed with some caution because there clearly is a range of views in the alliance about how to respond," he said. The split, he said, is between alliance members in eastern Europe and those in western Europe.
Germany and others in western Europe intend to block further U.S. efforts this year to give the go-ahead to put Georgia on a formal track toward membership, although they are leery of giving the appearance of caving in to Russia on this issue.
"There is a middle ground that I will suggest, where we do some prudent things that are consistent with the kinds of activities NATO has been engaged in for nearly 60 years in terms of planning, in terms of exercises - and at the same time are not provocative and don't tend to draw any firm red lines or send signals that are unwanted, at the same time it provides some reassurance to the allies in eastern Europe and the Baltic states."
Gates also said that while Russia's more aggressive actions, including its incursion into Georgia, are worrisome to many in NATO, there is no expectation of war with Russia.
"It's hard for me to imagine that those who are currently in NATO feel a real military threat coming from Russia," he said. "To the degree there is a sense of concern, my guess is it has more to do with pressure and intimidation than it does with any prospect of real military action."
NATO Secretary-General Jaap de Hoop Scheffer and envoys from all 26 member countries were in Georgia this week. The NATO delegation visited the central Georgian city of Gori, which was bombed and occupied by Russian troops during the five-day war in August.
Russia's Foreign Ministry said the Gori visit sent an obvious anti-Russian message. The NATO chief would have gotten a more objective picture by visiting the capital of South Ossetia, which came under heavy Georgian shelling during the war, the ministry said.
In remarks Thursday at the Royal United Services Institute for Defence and Security Studies, de Hoop Scheffer said, "I do not believe the second Cold War is in the offing but the role Russia wants to play in the international system is uncertain."
"Russia has demonstrated a total disregard for the sovereignty of a small neighbor, and for international law," the NATO chief added. "This represents a challenge for our partnership. Russia has long demanded to be treated with respect. That respect has to be earned."