Then, clearly, you alternative to a UN is every state for itself. And no state answerable to any other (well, except maybe the ones holding a big club).
The global state of affairs is essentially anarchic. Have always been so despite the UN attempt.
Anarchy does not mean mindless violence and chaos. Anarchy -- at its core -- is about non-hierarchical relationships. No one is above another by way of institutionalized stratification (classes).
That does not mean I am so naive as to believe that there are no non-institutionalized forms of order and classes. Just as individuals are not the same, so are countries not the same. Some people are taller than others, some countries are more powerful than others. If the world is a basketball game, then tall people will have advantages and would be considered first choice draft picks. Likewise, security and strength have always been the first considerations for any country, powerful countries will naturally be seen as leaders in some ways.
Everyone have an emotionally and politically charged subject, so I will use Viet Nam as example.
The UN failed in Viet Nam. After WW II, the plan was to put Indochina under UN administration towards independence. It was a noble idea. Peaceful and workable.
The UN failed, not because the organization actually failed the execution of that plan, but failed in that once the Viet and Chinese communists and France were determined to deviate from what the war powers (US, Britain, China, and Russia) agreed upon, that organization was impotent in getting the course of the region back to the original plan. So in a manner of speaking, it was not so much the UN as an organization failed but that it was the UN as an idea that failed. In the end, no one answered to anyone. The powerful US was just as helpless as the weaker Viet Nam, helpless in the sense that everyone was beholden to themselves, as in self interests, and not to a higher authority, such as the UN or God. A civil war resulted in Viet Nam, and the world got closer to a nuclear showdown between nuclear superpowers.
The bottom line is that no one believed in the UN as a noble idea and believes in that idea powerful enough to sacrifice their own self interests. As long as there are discrete citizenry, American, Russian, Chinese, French, English, and so on, self interests will always override global interests.
Or to put it another way...
https://www.amazon.com/Rage-Nations-World-Twentieth-Century/dp/0802844553
An excellent read.
"Long enough" .... based on what and for what? Why not ten more/fewer years?
That the UN has been a factor in every country's foreign affairs is hardly a disqualifier: that's exactly what the UN was intended to be.
Take the idea of nuclear weapons non-proliferation. The UN failed to prevent India and Pakistan from becoming nuclear weapons states.
I am not saying that being a factor in every country's foreign affairs is a disqualifier by itself. You
ARE correct, and I say that with emphasis. But I would have more enthusiastic support for the UN if somehow the organization, as a factor in every country's foreign affairs, is an effective player/factor/influence, especially on a major issue like nuclear weapons.
Now...If there are Indian and Pakistani objections, public posts or private thoughts, to what I said, then we have just seen the reason why the UN as an idea have been and will remain unworkable. To these respective citizenry, their nations' concerns are legitimate and, as they believed, powerful enough to override UN objections. But then that is exactly my point.
Assuming, for the moment, no one has a problem with the purposes of the UN (irrespective of the organisation):
<snipped>
Then how could states achieve this?
(The discussion is alltogether different if you don't agree with the purposes)
But I do agree with purposes stated.
The problem is -- look at the book -- nationalism.
I am a citizen of the world's most powerful country -- US. For a citizen of a weaker country, why should he/she support a global organization if he/she believes US-UN ideals are inappropriate, not merely inapplicable, for his/her country ?
Take the idea of 'international law', for example.
What law(s) should be made 'international' in scope, therefore, qualify for enforcement ?
Currently, China is giving Chinese version of the middle finger to the UN regarding the South China Sea. And not a single PDF Chinese member deviate from that defiant position. Am not saying that as a criticism towards the Chinese members of this forum. Am saying that as an example of how a nationalistic idea can become personally engaged and engaged to the point where that idea is unshakable in conviction.
A nationalist may believe in the nobility of UN principles as you cited, but only as long as the
APPLICATION of those noble ideas do not conflict with his country's self interests.