What factors define independence or sovereignty in 2010+?
Legislative independence from others? (eg "Brussels", a popular topic in England)? But then how about international law (eg trade agreements being a topic of debate in the US these days)?
Capital autarky? Do foreign investments and/or trade deficit undermine sovereignty? Should countries make a distinction between investment by private vs state foreign investors?
Yet, unlike people & goods, pollution (CO2 or nuclear), birds, the wind, volcanic ash, earthquakes, etc do not need permissions to cross borders.
Once upon a time a city was the optimal size of a state - country. What Is the optimal size today? Continental? Global (planetary)?
PS. What about the independence of a country and the global economy from speculative global finance?