Governments have tried to solve it by various means throughout history. In some cases they have succeeded in keeping one country out of war while others continue to make war from time to time. Humanity still faces the threat. When the knowledge of how to do that is spread everywhere, to at least some persons in every social group, there will be world peace. In social theory, the basis for an argument by which to effect friendly persuasion of persons to abstain from war is quite simple and clear.
All persons live by being members of a species, specifically humanity.
No one is made by a particularly national production industry. In that life, all benefit from each other. No nation is isolated industrially except to its detriment and relative impoverishment. Therefore any damage to any group or place considered foreign is not only fratricidal, but also economically deleterious. The well-being of every person in whatever country depends on world peace if the maximum prosperity is to be enjoyed.