I liked your approach to understand geopolitics. Many people do not understand that there are big ramifications for such decisions. And morality of these decisions is always cloudy, regardless of whatever we decide. There are no simple answers.
While the citizenry can "move the needle" a little, the geopolitical decisions will happen in the back rooms of politics. We can hope that we have the best people in charge, but our electoral systems are faulty. There would be a much different outcome if the Russian had invaded during the Trump administration.
We need a system where we can find the better people. Check out my byline.