Comment by cjfd
Whether or not a 'LIO' exists is not that interesting to me. What is interesting is what actually exists and what has happened in history. What actually exists is an enormous shock after, for instance, world war one where the question arose how it is possible that basically an entire generation of young men was slaughtered. E.g., every small village in France has a memorial of the fallen soldiers during world war one. For many decades after the war commemoration were/are still being held. It used to be that competing for territory was just the normal thing countries did. Then, it became clear that this has a potentially enormous cost in human lives. The obvious conclusion for people who are not sleepwalking through life and through history, is that any political leader who advocates for a change in country borders and does so much as hint to violent means of doing so is totally deranged and immoral. A similar shock has gone through the world after world war two, which, for instance, lead to the creation of the declaration of universal human rights. Among the decent public, it is also concluded that a violation of human rights is deranged in immoral.
I'm not sure how this relates to the discussion.
I agree most countries, certainly western countries, have realized that waging the kind of wars like WW-I and WW-II is not a good idea. But there have been a lot of war and killing anyways since the world wars and there have been a lot of new borders redrawn and countries formed. In more recent times we have Putin invading Ukraine and the general instability of the post cold war Eastern Europe.
So the calculus has changed for many reasons. But "new order" is not one of them. The so called new order was a result of the calculus changing, not the other way around. Countries fight for power in other ways and other societal changes also influence their decisions. I.e. you are confusing cause and effect. Now we have different dynamics, not a collapse of world order, things have shifted very slightly. "The end of the world as we know it" gets a lot of clicks on social media but it's not like we're suddenly having WW-I all over again and it's not like that order you thought was absolute really was. It's just that's how the alignment of interests landed.