You answered your own question regarding a civil war, Serbian war crimnes against Albanians.
Violence was all one way, fascist Serbia was the country unleasing in on their neighbours.
Serbia would not have lost Kosovo if it did carry on it's tradition of war crimes there.
You are also ignoring the almost decade of war crimes by fascist Serbia in Coratia and Bosnia (Srebrinica, the worst mass killing since WW2, Sarajevo, 11000 killed by fasicst Serbian forces during their seige of the city) prior to their crimes against humanity in Kosovo that finally promted Nato intervention.
Nato putting an end to fascist Serbian war crimes was long overdue.
Very different to the Russian civil war now raging in Bilhorod.
