I found it hard to believe that a nation that lived in peace for decades would so violently break apart in a spasm of visceral hatred. Was the rape a consequence of the war or was it planned and premeditated? Why was the international community so slow to react to such a thing in Europe's corner?
In two words: Greater Serbia
This year will mark the 100th anniversary of an even greater disaster related to this unfortunate desire.
However, the Serbs were not the only ones to commit massacres and rapes, nor were they exclusively perpetrators, but also victims. Yet theirs is the responsibility for the majority of such crimes, as well as starting the conflict in which they happened.
Was the rape a consequence of the war or was it planned and premeditated?
Rape and murder against members of different religious, linguistic, and cultural communities have an unfortunate tradition in the Balkans. They go back for centuries, at least as far as the Ottoman occupation.
Some of the crimes, in particular the ethnic cleansing, must be said to have been premeditated. See e.g.
https://en.wikipedia.org/wiki/Memorandum_of_the_Serbian_Academy_of_Sciences_and_Arts
For the role of the media in generating ethnic hatred:
https://en.wikipedia.org/wiki/Role_of_the_media_in_the_Yugoslav_wars
And secret propaganda operations, to demean perceived enemies like Croatia: