OP-ED:

Russia chose to fight American-armed Georgia over the territory of South Ossetia - a piece of land the size of Rhode Island and containing only 70,000 people. Why? And what are the implications for the United States and Russia's neighbors?

In past centuries, South Ossetia has been part of both the Russian and Georgian empires. And both countries still covet its territory. Although the dust has not yet settled, Russia won and once again controls South Ossetia. It won because it is stronger and because no outside force would seriously contemplate sending troops to help Georgia fight Russia.

Russia's onslaught has shattered any illusions that Georgia may have harbored about the military and diplomatic benefits of its friendship with the West. Also gone is the notion that NATO could offer full membership to Georgia without risking confrontation with Russia. For both these reasons, Georgia is now less likely to become a member of the Atlantic alliance.

In the coming months, Russia may feel free to support South Ossetia's independence (despite a recent statement to the contrary) or even to organize a South Ossetian vote on becoming part of Russia. Similar Russian moves could be made in Abkhazia, another breakaway region of Georgia that was once under Russian sovereignty. Russia will claim, with some justification, that the people of South Ossetia and Abkhazia have long preferred to be minorities in Russia rather than Georgia. Because of their less than ideal centuries-long history with Georgia, both areas tried to leave Georgia and join Russia during the Soviet era.

Of course, Georgia will reject these Russian arguments on the grounds of their internationally recognized sovereignty over South Ossetia and Abkhazia. Much of the world will agree and protest any Russian action to enlarge its borders. But these protests will probably make no difference. Nations willing and able to use force have not often been restrained by those who confine themselves to diplomacy. And no one, save Georgia, will have the appetite to do much more than talk.

This does not mean that the West's reaction will have no impact. The stance that the United States and Europe take will be seen as a harbinger of possible Western responses to future Russian actions in other parts of the former Soviet Union. A weak response may be seen as a green light for provocative actions in Ukraine while a strong one may give Moscow pause.

Additionally, the smaller the cost of Moscow's victory in South Ossetia, the stronger the Russian nationalists - who back current Russian policy in Georgia - will become. This is important because their rising strength means increased Russian pressure in Belarus and Ukraine - countries dear to the nationalists because they are central to their dream of an expanded Russian state encompassing all the Slavic parts of the former Soviet Union. Even the majority of Russian officials, who do not believe this is a realistic goal, still believe that Russia should be the dominant power in the former Soviet space, and therefore will support a more aggressive policy in those places.

How is the West to react? With the power of Russian nationalists ascendant, it is especially important that the next administration, in consultation with Congress, decide where America will draw its red lines. This will involve sober judgments regarding U.S. national priorities (and where the current conflict ranks within them). It will also require a clear conception of the military and economic capabilities of the U.S. If we cannot do everything, what problems are most important and what countries are a necessary part of the solution? What price are we willing to pay for this cooperation? How much political and economic capital are we able and willing to spend in areas of the world: a) that are not critical to the central interests of the United States; or b) where we can't win at an acceptable cost?

An inability to firmly draw these red lines early in the new administration will increase the possibility that Russia or some other country will challenge vital American interests. No country should do so without fully understanding the risks of such behavior. Therefore, it behooves both the McCain and Obama national security teams to begin this definitional work now.

Herman Pirchner Jr. is president of the American Foreign Policy Council.