At the high minded level, you are correct. But pragmatically speaking, that is what we chose to recognize -- that to some respect, might make right.
Country A uses a landmark to attack Country B. Country B defeated A but in order to secure a peace, that landmark must be occupied and render ineffective for A.
The problem here is duration, as in how long is that occupation. The longer the occupation time, the stronger it becomes entrenched the thought that B sort of 'owns' that landmark. Nominally, if not legally. If the countries A and B came to some form of negotiated peace, then there would be informal pressure for B to give up that occupation, then eventually that pressure would become formal.