What’s your definition of victory that does not include the war being over?
When we're talking about a war to oust an enemy government (which is what, I remind you, the purpose of "The Iraq War" was), and in the course of the war in question our military has succesfully invaded the other country, decimated or scattered their military into nonexistence, occupied their capital city, destroyed their ruling regime, captured their former dictator who has since been executed, and engineered the creation and ratification of a new constitutional government, then I consider that the war is over.
Scattered (and strategically pointless, if not utterly nihilistic) postwar violence during the reconstruction/counterinsurgency phase doesn't add up to "the war isn't over" in my book. It adds up to us being in a (particularly messy) reconstruction/counterinsurgency. Different ball of wax. At the very least I wish we could acknowledge that (if it's a "war") it's a different war than the 2003 war against the Hussein government of Iraq, for crying out loud.
The problem with rejecting what I've just stated above (as I am sure you will) is that otherwise you can never really say ANY war is "over". Any the-war-is-over verdict can be instantaneously overturned by someone in the location in question being randomly violent. And that's silly.
To try to bring it back to the original topic: Is the Serbia war "over"? By the standards people seem to apply to "The Iraq War", I have to say the answer is no. There is still sectarian/ethnic violence in Serbia after all. (Isn't there? Has ALL ethnic violence in Serbia ceased? forever?) So who says that war is "over"? If you're consistent, you can't. But if you're consistent, you almost can't call any war "over" - as long as someone, somewhere in the country in question, is being violent. Which is indication of nothing if not having a bizarre, silly standard for when a war is "over", or "won". Which most people in the West now do, it seems.