Russia will not assault Tblisi. They’re not COMPLETELY nuts.
I charge that we now have an unequivocal answer. They will expand to dominate resources such as the Russian seizure of the Georgian oil pipeline, similar to how the immature fascist states of yesteryear sought territory.
In this case, the Russians deliberately escalated a situation seeking to cause a confrontation, which may in turn be another piece of the puzzle as to how they will act.
You say they won't assault Tbilisi. Tbilisi does not have to be occupied to control the oil lines. Though I still believe the Russians will, but we shall see.
The question is now, since we apparently won't do anything other than wring our hands, what country will be their next target. Noting this, it has to have a region they can encourage rebels within and some valuable resource worth having.
With that in mind we can develop a test. Will Russian backed rebel activity start in one of the -stans? Will the Russians then use government suppression of rebels as an excuse to seize the resources? If so, we will know for certain the modus operandi for the expansion of a mature fascist state. My hypothesis to these questions is yes.
They don't need to "assault" Tblisi.
Think about it for a couple of minutes and look at the map.
As an example. If you were to blockade New York City's harbors, hold all the entry points to the bridges and tunnels for the city and then just maybe.... blow up a couple of pumping stations, power plants and sewage facilities....how long before New York ceases to be an organized city. 2 maybe 3 days, tops.
The Russians don't have to take Tblisi. They can take away the things that make Tblisi a city.