Presumably the principal "united we stand" applies to those 140 sovereign states.
Sovereignty includes the right of self determination—putting the interests of one particular state above the interests of the entire family of nations—the part before the whole. Here is a contradiction and a possible conflict of interest. Britain's Prime Minister Heath, like many another spokesman in his position, summed up the issue in the pithy phrase: "British interests come first."
If the French, Italian, Japanese and other prime ministers take a similar stand, implied by the principle of sovereignty, situations are bound to arise in which the interests of two or more nations clash, opening the way for conflicts at many levels: differences of interpretation, negotiations in the course of which concessions may be made by both parties. The differences may be settled by diplomats sitting around conference tables or by armies on the battlefield.
With 140 sovereign states on the planet, the probability of conflict would seem to be overwhelming. As a matter of daily experience such confrontations and conflicts do occur. Most of them are handled by negotiation. A few lead to armed struggle.
Since 140 sovereign states exist on one earth, means must be found that will enable them to co-exist, if possible, without conflict, and certainly without military conflict. The means generally relied upon today for dealing with such problems is negotiation between representatives of all parties at interest. At the national level this would mean negotiations between representatives of the involved governments.
Negotiations between representatives of various governments are always going on—dealing with political, economic and cultural issues. Within each nation such negotiations are conducted between spokesmen for various government departments. Internationally they are conducted by representatives of various governments working through their diplomatic or consular services. Within each nation and between nations confrontations may be settled by negotiation. At each level they may result in armed conflict.
Governments exist to deal with conflicts and, where possible, to resolve them before they reach the shooting stage. This is notably true in domestic affairs because there are usually public officials charged with the duty of dealing with problems. Internationally, unless there is an international agency such as the Universal Postal Union of the Organization of American States, the issue must be settled by special representatives of the parties.
The argument for a world government begins with the assumption that means should exist to deal with international issues before they reach an acute stage. Such means exist within each local government. Similar arrangements should exist at the international level to deal with issues that arise between governments.
The political core of a social stage beyond civilization will be a planet-wide, international, regional and local network of institutions, integrated, coordinated and administered on the federal principle: local affairs controlled locally; regional affairs controlled regionally; international affairs controlled by a planet-wide political authority. Such a relationship would imply states rights for the local authority; regional rights for the regional authority, and full awareness in the central authority of the possibility, at this juncture, of establishing order, justice and mercy on the planetary level—in our present terminology, a "world government."
Basic to this federal structure would be the Jeffersonian assumption: "That government governs best which governs least", with an amendment: "provided that the authority in question governs sufficiently to establish and maintain physical health, social decency, order, justice and mercy in reasonable proportions throughout the area subject to its jurisdiction".