I think the solution is to have enough renewable energy for all of humanity.

Humans are gonna human unfortunately. Biologically I’m not convinced we are capable of eliminating war because humans are competitive by nature. To the point that there will always be one group or another trying to force its ideals onto another.

I’ve often thought about “what if we could snap our fingers and every weapon beyond that of a spear (technologically) was vanished, and any/every attempt to fashion something deadlier would fail/poof out of existence as well.”

That might stave off large scale war but there would still be tribal warring on a smaller scale I fear. Plus a ton of other issues that would arise from suddenly having no guns/missiles/projectiles/etc.

Like others said, struggle is in human nature. But it is possible to shift it to other domains: art, science, exploration. To prevent this stuggle spill back into physical violence, there should be broad consensus on basic rules, effectively enforced.

So I’d say, build this consensus, which will probably need to rely on abundant renewable enengy, some form of UBI, equality, and stronger international institutions, but will not spotaneously evolve towards unsupportable preferences of some groups.

Put all leaders together in a hall with good music and cozy interior and give everyone MDMA.

this is a bit grim but global-wide information control that shreds any information which will help the growth of the idea of overly patriotic but less enough to not kill the domestic culture (but i think, not necessarily always telling the truth). that will also promote the sense of global village and transnationalism. and relocate the idea of war to other rivalries like on sports or something, idk.

basically limit the free will without showing it. I can’t think if it’s gonna happen or this even possible.

Nuclear deterrent. If that fails, nuclear annihilation. Either way, there will be no more wars.

The question is ill-posed.

War is just a tool, a collective act of violence that a group of people do against another in order to obtain a result. It’s always sad and it’s always bring sufference, but one could say sometimes it’s necessary. If you cancel war from the world witouth changin anything else, you will ends up probably damagin more the one with actually less power, since violence is usually the last resort in order to confront someone that hold political, economical and soft power upon you.

If you wanted to ask how we go to a situation when wars are not necessary and they are actually the less convenient and effective way to obtain collective or personal results, so that we ends up with no actual war are started, here’s my answer. We need to build a system that minimize close to zero the difference in power (every kind of power) between people, and we need to build an efficient an relieble system to intermediate and resolve the inevitable conflict between people and groups.

Let’s first address all the “nature” and “biological” not-really-true claims.

The Batek people of Malaysia are so averse of killing other humans that refuse to do it even when threatened with slavery https://peacefulsocieties.uncg.edu/societies/batek/

So, war is cultural, not biological.

Second, why do we do war?

At first glance, is for scarce resources, for survival.

But look at the modern wars. Are they for survival? Are they for resources that we need to survive?
No they are not.
They are for power.

But whose power?
The power of those who actually have to fight and die?
Certainly not.

The power of the rulers, who are greedy for more power.

Most people need to be scared into going to war, need to be convinced that they are defending their families and their “people”.

This is why rulers work very hard to build national identities, the good “us” vs the evil “them”.

Here we need three things:

1. We need a culture that knows how to recognize those greedy for power, those with a desire to dominate, and see them as the threat to freedom that they are, ie some sort of https://en.wikipedia.org/wiki/Leveling_mechanism
   There are several cultures that do that, but it has to be a deliberate and conscious thing.

2. We need to rethink our identities, national and not, because those identities are used to define the “other” that is ok to harm and kill.
   A way to do this is to make sure that people who want to travel and visit other groups can do so easily: this will help the various groups understand and humanize each other.

3. We need a culture that stresses the importance of non-violent conflict resolution.
   Because if all you know is violence, then that’s what you will use.

I mean, easier said than done of course, but I think that knowing the direction makes it easier to reach it.

For further reading on the subject, I would recommend Bob Altemeyer’s “The Authoritarians” and Graeber & Wengrow’s “The Dawn of Everything” from the top of my head.

A death match between the presidents / prime ministers of the rival countries. The country of the winner of that match will win the war, and the country of the loser has to deal with the following consequences.

Well effectively, it would entail an all-encompassing global spying machine that gathers all data possible, and imprisons anyone who deviates from the expected baseline. (Wouldn’t end well for me either.) You have to remove most individuality to remove reasons for fighting. And even if you imprison 999 false leads to capture just one instigator, that’s the only way to ‘guarantee’ a fairly high level of security.

So what I’d say we need is 1984 or Мы levels of oversight to have any chance of curtailing conflict for good.

EDIT: oh, and re-education. Lots and lots of re-education.

No hands for anyone. Possibly no feet too. Only the cooperative will survive.

Simple. We make war illegal.

Impossible. You can only deter and mitigate risk. But war is in our nature. War is uniquely human because it requires at least one civilization to wage.

The only way to stop war on Earth is to convince everyone here to go to war somewhere else.

So my plan is to militarize the school systems, manual military or scientific service at 18, create a federated republic under an international parliament, nationalize systems and get away from “profit” in exchange for progress, and go to war with the unknown to find “God” or whatever. Everyone who cant/wont can get UBI and healthcare and education a plenty, create art to their hearts content and do the “culture” thing.

Rename to “armed conflict” or “special military operations”

This is something my old history teacher once mentioned: we have games like COD and other esports titles. Just have all conflicts resolved via virtual combat instead of in real world violence