That's the clearest message I can think of from the Russian attack on Georgia, no matter what the precise details of its onset may have been. If you're small and can't take care of yourself, no-one else will do it for you. They may wring their hands and bemoan your fate, and then again, they may not; neither will be of much use.
The second lesson is that the human story continues unabated. All this talk about international law, international organizations, international courts - they all have their uses, of course, and none of them are going to make history stop trundling along in its traditional ruts. Might often makes right, regrettable as that may be. And if the might is being wielded by the right (=wrong) side, even the most outspoken propagandists of the Internationalism Narrative will forget their principles in favor of their dislikes. (Translation: if the bully is acting against America's interests, let us see if we can't justify his being a bully. In the Leader of the Guardian, no less).