Arguably the greatest book on political realism in the 20th century was University of Chicago Professor Hans J. Morgenthau's Politics Among Nations: The Struggle for Power and Peace, published in 1948. In that seminal work, Morgenthau defines the status quo as "the maintenance of the distribution of power that exists at a particular moment in history." In other words, things shall stay as they are. But it is not quite that clear. For as Morgenthau also explains, "the concept of the 'status quo' derives from status quo ante bellum," which, in turn, implies a return to the distribution of power before a war. The war's aggressor shall give up his conquered territory, and everything will return to how it was.
The status quo also connotes the victors' peace: a peace that may be unfair, or even oppressive, but at the same time stands for stability. For a change in the distribution of power, while at times just in a moral sense, simply introduces a measure of instability into the geopolitical equation. And because stability has a moral value all its own, the status quo is sanctified in the international system.