Johannes: I think that the real question is whether self-determination, which in the current context means national self-determination, is good from the Left's point of view. Frankly, I have doubts. National boundaries are quite permeable by the capital, they tend to divide mainly the workers.
Please also note that the guardians of "national identity" are almost always the ruling and and the scribbling classes - e.g. the recent surge of Serb nationalism was instigated "from above" - by intellectuals and politicians.
My own position on this issue is close to that of Rosa Luxemburg, who opposed national separatism on the grounds that it divides the working class.
Wojtek