you´re absolutely right that most of the americans dont know the difference between the balcan nations, but more then a half of those americans would also say that europe is the capital of nebraska or something like that.
some mods mind historical facts, others do not.

croatia is a independant kingdom untill 1102 (personal union with hungary)
serbia is a independant kingdom untill 1389 (epic battle of kosovo polje)

greetings from lijepa nasa to my serbian brothers !!!