All these tensions -- between Russia and the West, between Georgia and its breakaway republics -- are fuel for this week's fighting, and reasons the violence may be hard to contain.
"It's clearly very unstable and dangerous," said Andrei Kortunov, president of the New Eurasia Foundation in Moscow. "I don't think we'll be able to get back to square one. This has already created something that is not going to fade away easily, this resentment and hostility."
If Russia were to engage in a full-on military conflict with Georgia, analysts say, the battle would probably be protracted and bloody.
Although Georgia is far smaller and poorer than Russia, the Georgian military has been refurbished with training and equipment from the United States. Georgian soldiers would also have the advantage of fighting on familiar mountain terrain well-suited for guerrilla tactics.
David L. Phillips, a senior fellow with the Atlantic Council of the United States think tank, said he spoke with Saakashvili about six weeks ago. The Georgian leader argued that his military would stand a fighting chance against Russia, Phillips said.
"Except for Russia's superior air power, he's of the belief that they can go toe to toe with Moscow," Phillips said.
Many analysts said that Russia, glutted with oil and gas profits and enjoying a stability unprecedented in recent years, has little strategic interest in a war with Georgia. Despite the Cold War-style rhetoric, Russia values its ties to the U.S. too much to damage them over a relatively minor issue such as South Ossetia.
But, they warn, Russia may have little choice. Moscow is eager to demonstrate dominance in the region. Moreover, it will be difficult for Russia to stomach attacks on South Ossetians, most of whom have been made Russian citizens and granted passports.
"So many times we said we're going to support the Ossetians. To now say, 'OK, guys, you lost the war, you have to be part of Georgia,' is impossible," Russian military analyst Pavel Felgengauer said.
And Russia is already losing men. At least 10 soldiers were killed in Friday's fighting, and dozens more wounded, Russian officials said.
"Of course there will be a response," said Putin, speaking on the sidelines of the Olympics in Beijing.
"We will not allow the deaths of our compatriots to go unpunished," Russian President Dmitry Medvedev said in Moscow. "Those who are guilty will be duly punished."
Around the same time, Russian warplanes launched airstrikes on several Georgian towns, according to Georgian witnesses, and Russian army units were sent over the border. Later in the day, Russian planes reportedly bombed Georgian air bases.
Russian news reports referred to the fresh army units headed into South Ossetia from Russia as "reinforcements." South Ossetian leaders told Interfax the arrival of new fighters was helping them to recapture control of the capital from Georgian troops.
Saakashvili, meanwhile, ordered a full mobilization of all reservists, and told CNN that his government planned to call home the 2,000 Georgian troops currently serving with U.S.-led forces in Iraq.
"We all have to unite in this very important and difficult moment for our homeland, when our future and our freedom are under threat," Saakashvili said in a national address.
Times staff writers James Gerstenzang in Washington and Erika Hayasaki in New York, and special correspondent Tiko Ninua in Tbilisi, Georgia, contributed to this report.
(BEGIN TEXT OF INFOBOX)
Mountainous nation of 26,900 square miles (about one-sixth the size of California) in the Caucasus region between Russia and Turkey.
An estimated 4.6 million people, mostly Georgians but also minorities such as Russians, Azeris and Armenians. The nation is overwhelmingly Christian.
Absorbed into the Russian empire in the 19th century, Georgia sought independence with the fall of the czar but was invaded by the Red Army in 1921 and incorporated into the Soviet Union. Josef Stalin was a native of Georgia. With the collapse of the Soviet Union in 1991, Georgia became an independent nation. In recent years, it has increasingly been allied with the West, to the disquiet of Moscow. Georgia is seeking membership in NATO and has about 2,000 troops in Iraq.
The northern province has a population of about 70,000, mostly Ossetians with a minority of Georgians. It enjoyed broad autonomy within Soviet Georgia. It has largely run its own affairs since rebelling against Georgian rule in a 1991-92 conflict that killed more than 1,000 people. South Ossetians have voted for independence twice in referendums, but the territory has not gained widespread international recognition, leaving it in limbo. (Abkhazia, another region in Georgia, also has claimed independence.) Russia has peacekeepers in South Ossetia, but Georgia accuses them of siding with the separatists. Georgian President Mikheil Saakashvili has vowed to reassert authority over the breakaway republic.
Source: Times Staff and Wire Services