None, since no one took collective security very seriously, especially UK and France. Totally alien to their realist view of diplomacy. Besides, the League is toothless seeing as it had no SC equivalent, to say nothing of an ATL Chapter VII of the UN Charter. It's pretty much ASB for either of those to be in place, because that would mean taking collective security seriously and not reducing military forces by 80% postwar... Kissinger lays all this out in granular detail in Diplomacy.